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Innervation
Kinds of Innervation Terms modified by Innervation Selected AbstractsInnervation of interneurons immunoreactive for VIP by intrinsically bursting pyramidal cells and fast-spiking interneurons in infragranular layers of juvenile rat neocortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002Jochen F. Staiger Abstract Cortical columns contain specific neuronal populations with characteristic sets of connections. This wiring forms the structural basis of dynamic information processing. However, at the single-cell level little is known about specific connectivity patterns. We performed experiments in infragranular layers (V and VI) of rat somatosensory cortex, to clarify further the input patterns of inhibitory interneurons immunoreactive (ir) for vasoactive intestinal polypeptide (VIP). Neurons in acute slices were electrophysiologically characterized using whole-cell recordings and filled with biocytin. This allowed us to determine their firing pattern as regular-spiking, intrinsically bursting and fast-spiking, respectively. Biocytin was revealed histochemically and VIP immunohistochemically. Sections were examined for contacts between the axons of the filled neurons and the VIP-ir targets. Twenty pyramidal cells and five nonpyramidal (inter)neurons were recovered and sufficiently stained for further analysis. Regular-spiking pyramidal cells displayed no axonal boutons in contact with VIP-ir targets. In contrast, intrinsically bursting layer V pyramidal cells showed four putative single contacts with a proximal dendrite of VIP neurons. Fast-spiking interneurons formed contacts with two to six VIP neurons, preferentially at their somata. Single as well as multiple contacts on individual target cells were found. Electron microscopic examinations showed that light-microscopically determined contacts represent sites of synaptic interactions. Our results suggest that, within infragranular local cortical circuits, (i) fast-spiking interneurons are more likely to influence VIP cells than are pyramidal cells and (ii) pyramidal cell input probably needs to be highly convergent to fire VIP target cells. [source] Effects of Direct Sympathetic and Vagus Nerve Stimulation on the Physiology of the Whole Heart , A Novel Model of Isolated Langendorff Perfused Rabbit Heart with Intact Dual Autonomic InnervationEXPERIMENTAL PHYSIOLOGY, Issue 3 2001G. André Ng A novel isolated Langendorff perfused rabbit heart preparation with intact dual autonomic innervation is described. This preparation allows the study of the effects of direct sympathetic and vagus nerve stimulation on the physiology of the whole heart. These hearts (n= 10) had baseline heart rates of 146 ± 2 beats min,1 which could be increased to 240 ±11 beats min,1 by sympathetic stimulation (15 Hz) and decreased to 74 ± 11 beats min,1 by stimulation of the vagus nerve (right vagus, 7 Hz). This model has the advantage of isolated preparations, with the absence of influence from circulating hormones and haemodynamic reflexes, and also that of in vivo preparations where direct nerve stimulation is possible without the need to use pharmacological agents. Data are presented characterising the preparation with respect to the effects of autonomic nerve stimulation on intrinsic heart rate and atrioventricular conduction at different stimulation frequencies. We show that stimulation of the right and left vagus nerve have differential effects on heart rate and atrioventricular conduction. [source] Identification and Characterization of Atrioventricular Parasympathetic Innervation in HumansJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2002KARA J. QUAN M.D. AV Parasympathetic Innervation.Introduction: We hypothesized that in humans there is an epicardial fat pad from which parasympathetic ganglia supply the AV node. We also hypothesized that the parasympathetic nerves innervating the AV node also innervate the right atrium, and the greatest density of innervation is near the AV nodal fat pad. Methods and Results: An epicardial fat pad near the junction of the left atrium and right inferior pulmonary vein was identified during cardiac surgery in seven patients. A ring electrode was used to stimulate this fat pad intraoperatively during sinus rhythm to produce transient complete heart block. Subsequently, temporary epicardial wire electrodes were sutured in pairs on this epicardial fat pad, the high right atrium, and the right ventricle by direct visualization during coronary artery bypass surgery in seven patients. Experiments were performed in the electrophysiology laboratory 1 to 5 days after surgery. Programmed atrial stimulation was performed via an endocardial electrode catheter advanced to the right atrium. The catheter tip electrode was moved in 1-cm concentric zones around the epicardial wires by fluoroscopic guidance. Atrial refractoriness at each catheter site was determined in the presence and absence of parasympathetic nerve stimulation (via the epicardial wires). In all seven patients, an AV nodal fat pad was identified. Fat pad stimulation during and after surgery caused complete heart block but no change in sinus rate. Fat pad stimulation decreased the right atrial effective refractory period at 1 cm (280 ± 42 msec to 242 ± 39 msec) and 2 cm (235 ± 21 msec to 201 ± 11 msec) from the fat pad (P = 0.04, compared with baseline). No significant change in atrial refractoriness occurred at distances > 2 cm. The response to stimulation decreased as the distance from the fat pad increased. Conclusion: For the first time in humans, an epicardial fat pad was identified from which parasympathetic nerve fibers selectively innervate the AV node but not the sinoatrial node. Nerves in this fat pad also innervate the surrounding right atrium. [source] Development of the swimbladder and its innervation in the zebrafish, Danio rerioJOURNAL OF MORPHOLOGY, Issue 11 2007G.N. Robertson Abstract Many teleosts including zebrafish, Danio rerio, actively regulate buoyancy with a gas-filled swimbladder, the volume of which is controlled by autonomic reflexes acting on vascular, muscular, and secretory effectors. In this study, we investigated the morphological development of the zebrafish swimbladder together with its effectors and innervation. The swimbladder first formed as a single chamber, which inflated at 1,3 days posthatching (dph), 3.5,4 mm body length. Lateral nerves were already present as demonstrated by the antibody zn-12, and blood vessels had formed in parallel on the cranial aspect to supply blood to anastomotic capillary loops as demonstrated by Tie-2 antibody staining. Neuropeptide Y-(NPY-) like immunoreactive (LIR) fibers appeared early in the single-chambered stage, and vasoactive intestinal polypeptide (VIP)-LIR fibers and cell bodies developed by 10 dph (5 mm). By 18 dph (6 mm), the anterior chamber formed by evagination from the cranial end of the original chamber; both chambers then enlarged with the ductus communicans forming a constriction between them. The parallel blood vessels developed into an arteriovenous rete on the cranial aspect of the posterior chamber and this region was innervated by zn-12-reactive fibers. Tyrosine hydroxylase- (TH-), NPY-, and VIP-LIR fibers also innervated this area and the lateral posterior chamber. Innervation of the early anterior chamber was also demonstrated by VIP-LIR fibers. By 25,30 dph (8,9 mm), a band of smooth muscle formed in the lateral wall of the posterior chamber. Although gas in the swimbladder increased buoyancy of young larvae just after first inflation, our results suggest that active control of the swimbladder may not occur until after the formation of the two chambers and subsequent development and maturation of vasculature, musculature and innervation of these structures at about 28,30 dph. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Noradrenergic Innervation of the Ventromedial Hypothalamus is Involved in Mating-Induced Pseudopregnancy in the Female RatJOURNAL OF NEUROENDOCRINOLOGY, Issue 8 2006L. E. Northrop The ventromedial hypothalamus (VMH) is an oestrogen-responsive area known to facilitate female sexual behaviour in the rat. The VMH is innervated by noradrenergic neurones projecting from the brain stem, and it has been demonstrated that noradrenaline receptor activation in the VMH plays a role in the expression of the lordosis reflex. Noradrenaline has been shown to be released within the VMH after a female receives vaginocervical stimulation (VCS) from the male during mating. VCS also is required to induce twice-daily surges of prolactin (PRL) characteristic of early pregnancy or pseudopregnancy (PSP). To determine whether noradrenaline within the ventrolateral ventromedial hypothalamus (VMHvl) plays a facilitatory role in initiation of PSP, we administered the ,1 -noradrenergic receptor agonist, phenylephrine, and the ,2 -autoreceptor antagonist, yohimbine, unilaterally into the VMHvl. Phenylephrine stimulated PSP in 85.7% of females given an amount of VCS known to be subthreshold for the induction of PSP, whereas saline infusion (0%) or cannula misplacement (7.7%) were ineffective. Yohimbine had a similar effect, inducing PSP in 85.7% of females, whereas 7.6% of both control groups together showed PSP. Finally, bilateral blockade of ,1 -receptors using prazosin blocked PSP in 100% of females given sufficient VCS to induce PSP, whereas saline infusion or misplaced intracerebral cannulae failed to prevent PSP in any animal. In all experiments, vaginal dioestrous was indicative of PSP, in that animals showed a mean number of days between oestrus of 12.8 ± 0.9. The results of the study demonstrate an important role for the VMHvl in initiation of PSP and suggest that the release of noradrenaline in the VMHvl at the time of mating contributes to neuroendocrine mechanisms responsible for establishing PSP in the female rat. [source] Dual Excitatory and Inhibitory Effects of Stimulation of Intrinsic Innervation of the Anterior Pituitary on Adrenocorticotropic Hormone Release in the RatJOURNAL OF NEUROENDOCRINOLOGY, Issue 1 2004L.-Z. Gao Abstract The gland cells of the mammalian anterior pituitary are innervated by substantial amounts of nerve fibres, and there is evidence that the nerve fibres are functionally active. In the rat, the nerve fibres make typical excitatory synapses with corticotropes. The physiological significance of this synaptic relationship was investigated in the present study. The anterior pituitary of the rat was sliced and stimulated with electrical field in a chamber. The perfusate was continuously collected and immunoradioassayed for adrenocorticotropic hormone (ACTH). When the gland slices were stimulated at a high frequency of 10 Hz, there was a significant inhibition of ACTH secretion. Stimulation at a low frequency of 2 Hz resulted in a quick and transient excitation of ACTH release. The results indicate that stimulation of the nerve fibres in the anterior pituitary has dual excitatory and inhibitory effects on ACTH secretion. [source] Independence of Connexin Expression and Vasomotor Conduction from Sympathetic Innervation in Hamster Feed ArteriesMICROCIRCULATION, Issue 5 2004ROBIN C. LOOFT-WILSON ABSTRACT Objective: Vasomotor responses can travel along the wall of resistance microvessels by two distinct mechanisms: cell-to-cell conduction through gap junctions or the release of neurotransmitter along perivascular nerves. It is unknown whether vascular innervation influences the expression of connexin molecules which comprise gap junctions, or the conduction of vasomotor responses. In feed arteries of the hamster retractor muscle (RFA), the authors tested whether sympathetic denervation would alter the expression of connexin isoforms and the conduction of vasomotor responses. Methods: Using intact vessels with sympathetic innervation and those 7,8 days following denervation surgery, mRNA expression was quantified using real-time PCR, cellular localization of Cx protein was characterized using immunohistochemistry, and vasomotor responses to dilator and constrictor stimuli were evaluated in isolated pressurized RFA. Results: Connexin protein localization and mRNA expression were similar between innervated and denervated vessels. mRNA levels were Cx43 = Cx37 > Cx45 , Cx40. Vasodilation to acetylcholine conducted ,2000 , m along innervated and denervated vessels, as did the biphasic conduction of vasoconstriction and vasodilation in response to KCl. Vasoconstriction to phenylephrine conducted < 500 , m and was attenuated (p < .05) in denervated vessels. Conclusions: The profile of connexin expression and the conduction of vasomotor responses are largely independent of sympathetic innervation in feed arteries of the hamster retractor muscle (RFA). [source] Variance of Peptidic Nerve Innervation in a Canine Model of Atrial Fibrillation Produced by Prolonged Atrial PacingPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2008XIUFEN QU Ph.D. Background:Long-term rapid atrial pacing may result in nerve sprouting and sympathetic hyperinnervation in atrial fibrillation (AF) in dogs. Whether peptidic nerve is involved in neural remodeling is unclear. Method and Results:We performed rapid left atrial pacing in six dogs to induce sustained AF. Tissues from six healthy dogs were used as controls. Nerve was identified by immunocytochemical techniques. The degree of nerve innervation was quantified by measuring the amount of staining area for each antibody and the heterogeneity of nerve distribution was qualitatively studied. In dogs with AF, the density of growth-associated protein 43 (GAP43) immunopositivenerve fibers in the left atrium (LA), atrial septum (AS), and right atrium (RA) was significantly (19,454.31 ± 1,592.81 ,m2/mm2 vs 1,673.41 ± 142.62 ,m2/mm2P < 0.001, 3,931.26 ± 361.78 ,m2/mm2 vs 1,614.20 ± 140. 41 ,m2/mm2 P < 0.05 and 2,324.15 ± 1,123.77 ,m2/mm2 vs 1,620.47 ± 189.05 ,m2/mm2 P < 0.05, respectively) higher than the nerve density in control tissues. The density of (neuropeptide Y) NPY-positive nerves in the, AS, and RA was (13,547.62 ± 2,983.37 ,m2/mm2 vs 703.72 ± 287.52 ,m2/mm2 P < 0.01, 2,689.22 ± 340.93 ,m2/mm2 vs 651.7 ± 283.02 ,m2/mm2 P < 0.01 and 1,574.70 ± 424.37 ,m2/mm2 vs 580.42 ± 188.12 ,m2/mm2 P < 0.001, respectively) higher than the nerve density in control tissues. At the same time, vasoactive intestinal polypeptide (VIP) positive nerve innervation shrank in dogs with AF. The density of VIP positive in LA, AS, and RA was statistically lower than the nerve density in control tissues, respectively. (110.48 ± 45.63,m2/mm2 vs 1679.32 ± 1020.34,m2/mm2 P < 0.01, 265.92 ± 52.51 ,m2/mm2 vs 2602.68 ± 1257.16,m2/mm2 P < 0.001 and 609.56 ± 139.75,m2/mm2 vs 2771.68 ± 779.08,m2/mm2 P < 0.01, respectively) Conclusions:Combined with VIP-ergic nerve denervation, significant nerve sprouting and NPY-ergic nerve hyperinnervation are present in a canine model of sustained AF produced by prolonged atrial pacing. [source] Patterns of Innervation of the Anterior Maxilla: A Cadaver Study with Relevance to Canine Fossa Puncture of the Maxillary Sinus,THE LARYNGOSCOPE, Issue 10 2005Simon Robinson FRACS Abstract Objectives/Hypothesis: Complications from canine fossa puncture of the maxillary sinus are caused by damage to the anterior superior alveolar nerve (ASAN) and the middle superior alveolar nerve (MSAN). The aim of this study was to elucidate the pattern of ASAN and MSAN within the anterior maxilla and to secondly determine suitable surgical landmarks to aid in accurately localizing the area of the canine fossa least likely to produce complications when a trocar is passed into the maxillary sinus. Methods: Anatomic dissection of the anterior face of the maxilla from 20 cadaver heads was performed. The pattern and presence of the ASAN and MSAN was identified on each side and tabulated. Landmarks for the safest entry point for canine fossa puncture were determined, and each side had a puncture placed using these landmarks. Any disruption of nerves was noted. Results: Multiple differing patterns of ASAN were identified. The ASAN emerged from its foramen as a single trunk in 30 (75%) sides and in a double trunk in 10 (25%). In 24 (60%), single or multiple branches from the ASAN trunks were identified. A MSAN was identified in 9 (23%) maxillae. The safest entry point for a canine fossa puncture was where a vertical line drawn through the mid-pupillary line was bisected by a horizontal line drawn through the floor of the pyriform aperture. Conclusions: There is significant variation in the pattern of ASAN and MSAN within the anterior face of the maxilla. By using the newly described landmarks when performing a canine fossa puncture, there is reduced risk of damage to these nerves and provides a reliable point to enter the maxillary sinus. [source] Innervation of the Pelvic Limb of the Adult Ostrich (Struthio camelus)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2010T. El-Mahdy With 24 figures Summary The pelvic limb of the ostrich is innervated by the lumbar and sacral plexuses. The lumbar plexus gave rise to several nerves (N.s) including, N. coxalis cranialis, lateral and cranial femoral cutaneous N.s, N. femoralis, cranial, caudal and medial crural cutaneous N.s, and N. obturatorius. The remaining nerves emanated from the sacral plexus. The N. iliotibial, N. ischiofemoralis, N. iliofibularis, and N. coxae caudalis were distributed in the thigh, while the N. ischiadica, which terminated as the tibial and fibular N.s that innervated the leg and foot. The tibial N. gave rise to the parafibular N. then divided to form the Nn. suralis medialis and lateralis. The N. suralis medialis continued as the N. metatarsalis plantaris medialis. The parafibular N. continued as the N. plantaris lateralis, which terminated as the R. digitalis of the fourth digit. The fibular N. terminated as the superficial and deep fibular N.s. The superficial fibular N. continued as the N. metatarsalis dorsalis lateralis and divided into two digital N.s to the third and fourth digits. The deep fibular N. crossed the ankle joint and continued as the N. metatarsalis dorsalis medialis that continued as the R. digitalis of the third digit. In general, the innervation of the pelvic limb of the ostrich was similar to the pelvic limbs of several different species of domesticated birds, including the chicken. We discuss the few differences as well as appropriate sites to perform nerve blocks for the lateral and medial dorsal and the lateral plantar N.s. [source] Immmunohistochemical Study of the Blood and Lymphatic Vasculature and the Innervation of Mouse Gut and Gut-Associated Lymphoid TissueANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2007B. Ma Summary The blood and lymphatic vascular system of the gut plays an important role in tissue fluid homeostasis, nutrient absorption and immune surveillance. To obtain a better understanding of the anatomic basis of these functions, the blood and lymphatic vasculature of the lower segment of mouse gut and several constituents of gut-associated lymphoid tissue (GALT) including Peyer's patch, specialized lymphoid nodules in the caecum, small lymphoid aggregates and lymphoid nodules in the colon were studied by using confocal microscopy. Additionally, the innervation and nerve/immune cell interactions in the gut and Peyer's patch were investigated by using cell surface marker PGP9.5 and Glial fibrillary acidic protein (GFAP). In the gut and Peyer's patch, the nerves have contact with B cell, T cell and B220CD3 double-positive cells. Dendritic cells, the most important antigen-presenting cells, were closely apposed to some nerves. Some dendritic cells formed membrane,membrane contact with nerve terminals and neuron cell body. Many fine nerve fibres, which are indirectly detected by GFAP, have contact with dendritic cells and other immune cells in the Peyer's patch. Furthermore, the expression of Muscarinic Acetylcholine receptor (subtype M2) was characterized on dendritic cells and other cell population. These findings are expected to provide a route to understand the anatomic basis of neuron-immune regulation/cross-talk and probably neuroinvasion of prion pathogens in the gut and GALT. [source] Konstruktionsprinzipien an der Vorder- und Hinterpfote der Hauskatze (Felis catus).ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2005Zusammenfassung Die Innervationsverhältnisse an der Vorder- und Hintergliedmaße der Katze wurden erneut untersucht, um die Darstellung der Muskelinnervation zu komplettieren (Abb.1,4). Mit Hilfe von speziellen Bewegungsanalysen wird der Beitrag der Pfotenmuskeln beim Gleichgewicht, in der Fortbewegung sowie bei spezifischen Manipulationen an den jeweiligen Einzelphasen eines Bewegungszyklus ermittelt. Die funktionellen Überlegungen sind in Abb. 5,11 graphisch aufbereitet. Figure Abb. 1.,. Übersichtsschema vom Plexus brachialis der Hauskatze, Medialansicht (nach Roos, 1989). C6, C7, C8, T1 = Ventraläste der 6. bis 8. Hals- und des 1. Brustnerven; (T2) = gelegentlicher Zuschuß vom Ventralast des 2. Brustnerven. ax N. axillaris: ax + fakultativer Muskelast zum M. teres major, ax 1 Gelenkast an das Schultergelenk und Muskelast zum M. teres minor, ax 2 Muskeläste zur Pars scapularis und Pars acromialis des M. deltoideus, ax 3 weiterer Gelenkast zum Schultergelenk, ax 4 Muskeläste zum M. cleidobrachialis, ax 5 N. cutaneus brachii lateralis cranialis, ax 6 N. cutaneus antebrachii cranialis; mc N. musculocutaneus: mc1 Muskelast zum M. coracobrachialis und Gelenkast zum Schultergelenk, mc 2 Muskeläste zum M. biceps brachii und zum M. brachialis, mc 3 Gelenkast zum Ellbogengelenk, mc 4 N. cutaneus antebrachii medialis; me N. medianus: me 1 Gelenkast zum Ellbogengelenk, me 2 , me 8 Rami musculares: me 2 zum M. pronator teres, me 3 zum M. flexor carpi radialis, me 4, 4, zum Caput humerale des M. flexor digitalis profundus, me 5, 5, zum M. flexor digitalis superficialis, me 6 zum Caput radiale des M. flexor digitalis profundus, me 7 zum M. pronator quadratus, me 8 zum M. interflexorius dist lis, me 9 Hautast zum Karpalbereich, me 10 Ramus medialis, me 11 Ramus lateralis, me 12 N. digitalis palmaris I abaxialis, me 13 , me 15 Nn. digitales palmares I, II, III communes; ra N. radialis: ra 1 , ra 4 Rami musculares proximales: ra 1, 1, zum Caput longum des M. triceps brachii, ra 2 zum M. tensor fasciae antebrachii, ra 3 zum Caput laterale, Caput mediale und Caput accessorium des M. triceps brachii, ra 4 zum M. anconaeus, ra 5 Ramus profundus, ra 6 Gelenkast zum Ellbogengelenk, ra 7 , ra 8 Rami musculares distales: ra 7 zum M. brachioradialis und zu den Mm. extensores carpi radialis longus et carpi radialis brevis, ra 8 zum M. extensor digitalis communis, ra 8, zum M. supinator, M. abductor digiti primi longus, M. extensor digiti primi et secundi, M. extensor carpi ulnaris und M. extensor digitalis lateralis, ra 9 Ramus superficialis, ra 10 N. cutaneus brachii lateralis caudalis, ra 11 Ramus medialis, ra 12 Ramus lateralis, ra 13 N. cutaneus antebrachii lateralis, ra 14 N. dig talis I abaxialis, ra 15 , ra 17 Nn. digitales dorsales I, II, III communes, ra 18 Ramus communicans; s N. suprascapularis: s 1 Muskeläste zum M. supraspinatus, s 2 Gelenkäste zum Schultergelenk, s 3 Muskelast zum M. infraspinatus; ul N. ulnaris: ul 1 Muskelast zum M. anconaeus, ul 2 Gelenkast zum Ellbogengelenk, ul 3 , ul 6 Rami musculares: ul 3 zum Caput ulnare und ul 4 zum Caput humerale des M. flexor carpi ulnaris, ul 5,5, zum Caput humerale und ul 6 zum Caput ulnare des M. flexor digitalis profundus, ul 7 Ramus dorsalis, ul 8 sein Hautast, ul 9 N. digitalis dorsalis V abaxialis, ul 10 N. digitalis dorsalis IV communis, ul 11 Ramus palmaris, ul 12 Hautast zum Karpalbüschel und Karpalballen sowie Muskeläste zu den besonderen Muskeln der 5. Zehe, ul 13 Ramus profundus zu den tiefen Zehenmuskeln (siehe Abb. 2), ul 14 Ramus superficialis, ul 15 N. digitalis palmaris V abaxialis, ul 16 N. digitalis palmaris IV communis. Meßbalken 10 mm. Figure Abb. 2.,. Ramifikation der Nerven für die kurzen Zehenmuskeln der (linken) Vorderpfote der Hauskatze, Palmaransicht, schematisiert. Orientierungspunkte: 1 Os carpi accessorium, 2 Ligamentum accessoriometacarpeum, medialer Anteil; I , V Mittelfuß- und Zehenstrahlen; Umrisse des Sohlen- und der Zehenballen strichliert. me N. medianus: me 10 Ramus medialis und me 11 Ramus lateralis des N. medianus, me 12 N. digitalis palmaris I abaxialis. ul N. ulnaris: ul 7 Ramus dorsalis, ul 11 Ramus palmaris, ul 12 Muskelast zu M. abductor digiti V und M. flexor digiti V, ul 13 Ramus profundus, ul 14 Ramus superficialis, ul 15 N. digitalis palmaris V abaxialis, ul 16 N. digitalis palmaris IV communis, ul 17 N. metacarpeus palmaris V, ul 18 N. metacarpeus palmaris IV lateralis, ul 18, N. metacarpeus palmaris IV medialis, ul 19 Muskelast zu M. adductor digiti V und Mm. lumbricales IV und V, ul 20 N. metacarpeus palmaris III, ul 21 N. metacarpeus II, ul 22 Muskeläste zu M. adductor pollicis und M. flexor pollicis brevis. Weitere Muskeläste sind gekennzeichnet mit Quadraten zu den Mm. adductores II und V, mit Kreisen zu den Mm. lumbricales, mit Pfeilen zu den Mm. interossei manus. Figure Abb. 3.,. Übersichtsschema vom Plexus lumbosacralis der Hauskatze, Medialansicht. L4, L5, L6, L7, S1, S2, S3 = Ventraläste der 4. , 7. Lenden- und 1. , 3. Kreuznerven. f N. femoralis: f 1 N. saphenus, f 2,7 Muskeläste für f 2, 2, M. sartorius, f 3,5 Bäuche des M. quadratus femoris, f 6 M. pectineus, f 7 M. gracilis, f 8 Gelenkast zum (medialen) Femorotibial- und Femoropatellargelenk, f 9 Rami cutanei; fc N. fibularis (peronaeus) communis: fc 1 Muskelast für den M. fibularis longus (alternativer Ursprung strichliert); fp N. fibularis (peronaeus) profundus: fp 1,3 Muskeläste für fp 1 M. tibialis cranialis, fp 2 M. extensor digitalis longus, fp 3 M. extensor hallucis longus, fp 4 N. metatarsalis dorsalis, fp 5 Muskelast zum M. extensor digitalis brevis; fs N. fibularis (peronaeus) superficialis: fs 1, 1, Muskeläste zum M. extensor digitalis lateralis, fs 2 zum M. fibularis brevis, fs 3 Ramus lateralis, fs 4 Ramus medialis, fs 5 Nn. digitales dorsales communes II , IV, fs 6 Nn. digitales dorsales proprii für die 2. bis 5. Zehe; g N. glutaeus cranialis bzw. caudalis: g 1 zum M. glutaeus medius, g 2 zum M. tensor fasciae latae, g 3 zum M. glutaeus profundus, g 4 zum M. piriformis, g 5 M. glutaeus superficialis, g 6 M. glutaeofemoralis; is N. ischiadicus: is 1 Muskeläste zu den Mm. gemelli und M. obturatorius internus, is 2, 2, zum M. biceps femoris, is 3 zum M. semitendinosus, is 4 zum M. semimembranosus, is 5 zum M. abductor cruris caudalis (tenuissimus); ti N. tibialis: ti 1 N. cutaneus surae caudalis, ti 2 Gelenkast zum (lateralen) Femorotibialgelenk, ti 3,5 Muskeläste für ti 3 Caput mediale des M. gastrocnemius, ti 4 Caput laterale des M. gastrocnemius sowie M. flexor digitalis superficialis und M. flexor hallucis longus, ti 5,5, M. popliteus, M. flexor digitalis profundus, M. tibialis caudalis und M. soleus, ti 6 N. plantaris medialis, ti 7 N. plantaris lateralis, ti 8 Ramus profundus (s. auch Abb. 4), ti 9 Muskelast zum M. flexor digitalis brevis, ti 10 Nn. digitales plantares communes II , IV, ti 11 Nn. digitales plantares proprii für die 2. , 5. Zehe; ob N. obturatorius: ob 1,5 Muskeläste für ob 1 M. pectineus, ob 2 M. adductor longus, ob 3 M. adductor magnus, ob 4 M. gracilis, ob 5 M. obturatorius externus. Meßbalken 10 mm. Figure Abb. 4.,. Ramifikation der Nerven für die kurzen Zehenmuskeln der (linken) Hinterpfote der Hauskatze, Plantaransicht, schematisiert. Orientierungspunkte: 1 Tuber calcanei; II , V Mittelfuß- und Zehenstrahlen; Umrisse des Sohlen- und der Zehenballen strichliert. ti N. tibialis: ti 6 N. plantaris medialis, ti 7 N. plantaris lateralis, ti 8 Ramus profundus, ti 9 Muskelast zum M. flexor digitalis brevis, ti 10 Nn. digitales plantares communes II und III, ti 11 N. digitalis plantaris II abaxialis, ti 12 N. metatarseus plantaris V, ti 13 N. metatarseus plantaris IV lateralis, ti 13, N. metatarseus plantaris IV medialis, ti 14 Muskelast zu den Mm. adductores digiti II und V, ti 15 N. metatarseus plantaris III, ti 16 N. metatarseus plantaris II, ti 17 Muskelast zum M. abductor digiti V, ti 18 Muskelast zum M. quadratus plantae, ti 19 Stamm des N. digitalis plantaris communis IV und N. digitalis plantaris V abaxialis. Weitere Muskeläst sind gekennzeichnet mit hochstehenden Rechtecken zu den Mm. digitales flexores breves, mit Quadraten zu den Mm. adductores II und V, mit Kreisen zu den Mm. lumbricales, mit Pfeilen zu den Mm. interossei pedis. Figure Abb. 5.,. Statik der Hauskatze in Normalstellung (nach Roos, 1989) (Sk) Lage des Schwerpunkts des Körpers; das gefällte Lot, die Schwerelinie, trifft die Unterstützungsfläche, d.h. das Rechteck zwischen den Gliedmaßenspitzen. Figure Abb. 6.,. Prinzip der Zuggurtung an der Vorder- (rechts) und Hintergliedmaße (links) der Hauskatze. Das Schwerelot der Hintergliedmaße (Sh) aus dem Hüftgelenk und das Schwerelot der Vordergliedmaße (Sv) aus dem Rumpfschultergelenk treffen die Fußungsflächen der Hinter- bzw. Vorderpfote. Die zur Aufrechterhaltung des Gleichgewichts notwendige minimale Zuggurtung der Gelenke erfolgt durch folgende Muskeln: 1 kranialer Bauch des M. semimembranosus, 2 Mm. vastus lateralis, vastus medialis und vastus intermedius des M. quadriceps femoris, 3 M. soleus, 4 plantare Endsehnen der Mm. interossei pedis, 5 M. supraspinatus, 6 Caput laterale, Caput mediale und Caput accessorium des M. triceps brachii, 7 Caput ulnare des M. flexor carpi ulnaris, 8 Mm. extensorii carpi radialis longus und carpi radialis brevis, 9 palmare Endsehnen der Mm. interossei manus. Einzelheiten im Text. Figure Abb. 7.,. Dynamik der Vorderpfote der Hauskatze in der Fortbewegung. Obere Reihe: Diagramme der Schrittbewegung der Vorderpfote, nach Röntgenbildern auf dem Laufband (in Anlehnung an Caliebe et al., 1991, kombiniert und ergänzt, Ergänzungen strichliert). Untere Reihen: Änderung der Gelenkwinkel und daraus abgeleitete Kontraktionen, evtl. Superpositionen sowie Entspannung verschiedener Muskeln oder Muskelgruppen: Große dunkle Pfeile = Beginn der Kontraktion, kleine Pfeile = anhaltende Kontraktion, gestreifte Pfeile = Superposition, helle Pfeile = Beginn der Entspannung 1 Beuger des Karpalgelenks, 2 Strecker des Karpalgelenks, 3 Wirkung des M. flexor carpi radialis als Adduktor, 4 Wirkung des M. extensor carpi radialis als Abduktor der Vorderpfote, 5 M. flexor digitalis superficialis, 6 lange Zehenstrecker, 7 Mm. interossei manus, 8 entspannter M. flexor digitalis profundus (manus) läßt das Krallenbein in Schonstellung. Seqq: Sequenzen 1,35. Figure Abb. 8.,. Dynamik der Hinterpfote der Hauskatze in der Fortbewegung. Obere Reihe: Diagramme der Schrittbewegung der Hinterpfote, nach Röntgenbildern auf dem Laufband (in Anlehnung an Kuhtz-Buschbeck et al., 1994, maßstab- und synchrongerecht eingerichtet und ergänzt, Ergänzungen strichliert). Untere Reihen: Änderung der Gelenkwinkel und daraus abgeleitete Kontraktionen, evtl. Superpositionen sowie Entspannung verschiedener Muskeln oder Muskelgruppen: Große dunkle Pfeile = Beginn der Kontraktion, kleine Pfeile = anhaltende Kontraktion, gestreifte Pfeile = Superposition, helle Pfeile = Beginn der Entspannung 1 Beuger des Tarsalgelenks, 2 Strecker des Tarsalgelenks, 3 M. flexor digitalis superficialis (pedis), 4 lange Zehenstrecker, 5 Mm. interossei pedis, 6 entspannt bleibender M. flexor digitalis profundus (pedis). Seqq: Sequenzen 1,35. Figure Abb. 9.,. Vorderpfote der Hauskatze in ihrer Funktion als Fangorgan, schematisiert. Obere Reihe: Perspektivische Darstellung nach Beobachtung an Freilaufkatzen, teilweise ergänzt nach Röntgenbildern von Boczek-Funcke et al. (1998). Untere Reihen: Bewegungsablauf aufgelöst nach den drei Bewegungsebenen S = Sagittalebene, A Abduktion , Adduktion, R = Rotationsebene. Einzelheiten im Text. Seqq: Sequenzen 1,5. Wirkungslinien der aktiven Muskeln: 1 M. flexor digitalis superficialis, 2 M. extensor digitalis communis und M. extensor digitalis lateralis, 3 M. flexor digitalis profundus, 4 Mm. interossei manus, 4, seine axialen Bäuche, 4, seine abaxialen Bäuche, 5 M. adductor digiti V, 6 M. adductor digiti II, 7 M. adductor pollicis, 8 M. extensor pollicis et indicis, 9 M. abductor digiti V und M. flexor digiti V, 10 M. abductor pollicis longus, 11 M. abductor digiti II, 12 M. flexor pollicis brevis, 13 M. pronator teres und M. pronator quadratus, 14 M. brachioradialis und M. supinator. Figure Abb. 10.,. Spezielle Bewegungen der Hinterpfote vor (oben) und während des Spurtstarts (unten), schematisiert. Situation in der S , Ebene. 1,4 Muskeln in Unterstützungskontraktion: 1 zweiköpfiger M. gastrocnemius, 2 M. soleus, 3 M. extensor hallucis longus, 4 M. tibialis cranialis, 5 M. flexor digitalis superficialis, 6 Mm. interossei pedis, 7 M. extensor digitalis longus, 8 M. extensor digitalis brevis, 9 M. flexor digitalis profundus. Figure Abb. 11.,. Dynamik bei der Kletterhaltung der Hinterpfote der Hauskatze, schematisch. Links Grundhaltung, rechts Spreizung und Streckung der Zehen II , V; der Mittelfuß nimmt an der Spreizung nicht teil. Beteiligte Muskeln: 1 M. adductor digiti V, 2 M. adductor digiti II, 3 M. abductor digiti V, 4 axiale Bäuche der Mm. interossei II , V pedis, 5 abaxiale Bäuche der Mm. interossei II , V pedis. Einzelheiten im Text. Summary Principles of construction in the forepaw and hindpaw of the domestic cat (Felis catus). 4. Innervation of muscles and analysis of locomotion. The innervation relations of the fore- and hindlimb of the cat were newly investigated to complete the interpretation of the muscle innervation (Figs 1,4). By means of special motion studies the contribution of paw muscles was determined during balance, locomotion as well as under specific manipulation of the prevailing sincle phases of the motion cycle. The functional considerations are graphically prepared in Figs 5,11. [source] Adrenergic and Cholinergic Innervation of the Mammary Gland in the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2002A. FRANKE-RADOWIECKA Adrenergic and acetylcholinesterase-positive (AChE-positive) innervation of the mammary gland in the sexually immature and mature pigs was studied using histochemical methods. Upon examining the adrenergic and cholinergic innervation, the adrenergic innervation was found to be much more developed. The majority of both sub-populations of the nerve fibres studied was localized in the subcutaneous tissue of the mammary gland. Adrenergic and AChE-positive nerve fibres also supplied structures of the nipple (subcutaneous tissue, blood vessels, smooth muscles fibres) and glandular tissue (blood vessels, lactiferous ducts). The glandular tissue contained the smallest number of adrenergic and AChE-positive nerve fibres. No distinct differences were observed in the adrenergic and AChE-positive innervation of the porcine mammary gland between the juvenile and non-pregnant adult animals. [source] Innervation of the detrusor muscle bundle in neurogenic detrusor overactivityBJU INTERNATIONAL, Issue 7 2003M.J. Drake OBJECTIVE To evaluate the peripheral anatomical distribution of innervation within muscle bundles of the detrusor and the changes arising in neurogenic detrusor overactivity (DO). PATIENTS AND METHODS Full-thickness samples from the bladder dome of three cadaveric transplant organ donors and four people with neurogenic DO caused by spinal cord injury were compared. Systematic serial cryostat sections were stained using Masson trichrome and elastin techniques, and vimentin immunohistochemistry. A coherent image stack was generated for three-dimensional image reconstructions, which were displayed using mixed rendering (i.e. differing graphics for separate tissue components) to show peri- and intra-bundle innervation against the muscle fascicle framework. RESULTS Control specimens had a dense nerve supply. Muscle bundle innervation was derived by dichotomous branching from peri-bundle nerve trunks in the inter-bundle connective tissue. Transverse interfascicular branches entered bundles perpendicular to the long axis at the midpoint of the bundle. They gave rise to axial interfascicular branches, which distributed to the pre-terminal and terminal nerve fibres. All samples from patients with neurogenic DO had patchy denervation. The primary deficit was predominantly at the level of the terminal axial innervation and was cross-sectionally consistent along the longitudinal axis of the muscle bundle. CONCLUSION Patchy denervation may reflect a deficit at the level of the peripheral ganglia. Any contraction in the areas of denervation either occurs out of co-ordination with the rest of the bladder, or is co-ordinated by means of non-neural structures. The observation of fine muscle strands running between fascicles, and connective tissue anchoring structures, represent two hypothetical mechanisms by which such co-ordination might be effected. [source] Innervation of vastus lateralis muscleCLINICAL ANATOMY, Issue 5 2007S. Patil Abstract The lateral surgical approach to the proximal femur potentially damages the nerve supply to the vastus lateralis (VL) muscle. This study describes the detailed anatomy of the nerve supply to the VL muscle based on dissection of ten cadaveric lower limbs. In all specimens, a single nerve trunk arose from the femoral nerve, which is most subsequently divided into two main divisions. These divisions gave two branches each. These branches coursed from anteriorly and proximally to posteriorly and distally within the muscle. When the muscle was reflected anteriorly from its attachment to the linea aspera, there was no damage to its innervation. Splitting of the VL in the midlateral line of the femur, however, resulted in denervation of the posterior half of the muscle. Precise knowledge of the nerve supply to the VL will help avoid iatrogenic denervation of the muscle in surgical procedures at the proximal femur through the lateral approach. Clin. Anat. 20:556,559, 2007. © 2006 Wiley-Liss, Inc. [source] Innervation of the sacroiliac joint in rats by calcitonin gene-related peptide-immunoreactive nerve fibers and dorsal root ganglion neuronsCLINICAL ANATOMY, Issue 1 2007Yasuaki Murata Abstract The sacroiliac joint (SIJ) can be a source of low back pain. Calcitonin gene-related peptide (CGRP) has been reported to play a significant role in nociceptive processing. However, the occurrence of CGRP-immunoreactive (CGRP-ir) sensory nerve fibers in the SIJ has not been fully defined. The present study investigated CGRP-ir nerve fibers supplying the SIJ. CGRP-ir nerve fibers in the vicinity of the SIJ cartilage and CGRP-ir neurons in the bilateral dorsal root ganglia (DRG) were examined immunohistochemically by administering anti-CGRP antiserum to rats. The SIJ was decalcified and cut into sections, and the CGRP-ir fibers around the SIJ cartilage were counted under microscopy. In another group, fluoro-gold (F-G), a neural tracer, was injected into the SIJ from the dorsal or ventral side with dorsal or ventral denervation. The number of F-G-labeled CGRP-ir neurons was counted in individual DRG. CGRP-ir fibers were observed more frequently in the tissues adjacent to the cranial part of the SIJ surface. In the case of dorsal denervation (ventral nerve supply), the CGRP-ir neurons composed 18.2% of the F-G-labeled neurons. In the case of ventral denervation (dorsal nerve supply), the CGRP-ir neurons composed 40.9% of the F-G-labeled neurons. There was a statistically significant difference in the number of CGRP-ir neurons between the ventral and dorsal nerve supplies to the SIJ. The cranial part of the dorsal side could be the part most associated with pain in the SIJ. Clin. Anat. 20:82,88, 2007. © 2006 Wiley-Liss, Inc. [source] Mechanisms of osteoporosis in spinal cord injuryCLINICAL ENDOCRINOLOGY, Issue 5 2006Sheng-Dan Jiang Summary Osteoporosis is a known complication of spinal cord injury (SCI), but its mechanism remains unknown. The pathogenesis of osteoporosis after SCI is generally considered disuse. However, although unloading is an important factor in the pathogenesis of osteoporosis after SCI, neural lesion and hormonal changes also seem to be involved in this process. Innervation and neuropeptides play an important role in normal bone remodelling. SCI results in denervation of the sublesional bones and the neural lesion itself may play a pivotal role in the development of osteoporosis after SCI. Although upper limbs are normally loaded and innervated, bone loss also occurs in the upper extremities in patients with paraplegia, indicating that hormonal changes may be associated with osteoporosis after SCI. SCI-mediated hormonal changes may contribute to osteoporosis after SCI by different mechanisms: (1) increased renal elimination and reduced intestinal absorption of calcium leading to a negative calcium balance; (2) vitamin D deficiency plays a role in the pathogenesis of SCI-induced osteoporosis; (3) SCI antagonizes gonadal function and inhibits the osteoanabolic action of sex steroids; (4) hyperleptinaemia after SCI may contribute to the development of osteoporosis; (5) pituitary suppression of TSH may be another contributory factor to bone loss after SCI; and (6) bone loss after SCI may be caused directly, at least in part, by insulin resistance and IGFs. Thus, oversupply of osteoclasts relative to the requirement for bone resorption and/or undersupply of osteoblasts relative to the requirement for cavity repair results in bone loss after SCI. Mechanisms for the osteoporosis following SCI include a range of systems, and osteoporosis after SCI should not be simply considered as disuse osteoporosis. Unloading, neural lesion and hormonal changes after SCI result in severe bone loss. The aim of this review is to improve understanding with regard to the mechanisms of osteoporosis after SCI. The understanding of the pathogenesis of osteoporosis after SCI can help in the consideration of new treatment strategies. Because bone resorption after SCI is very high, intravenous bisphosphonates and denosumab should be considered for the treatment of osteoporosis after SCI. [source] Diadenosine tetraphosphate protects sympathetic terminals from 6-hydroxydopamine-induced degeneration in the eyeACTA PHYSIOLOGICA, Issue 2 2010C. H. V. Hoyle Abstract Aims:, To examine diadenosine tetraphosphate (Ap4A) for its ability to protect the eye from neurodegeneration induced by subconjunctival application of 6-hydroxydopamine (6-OHDA). Methods:, Intraocular neurodegeneration of anterior structures was induced by subconjunctival injections of 6-OHDA. Animals were pre-treated with topical corneal applications of Ap4A or saline. Results:, 6-OHDA caused miosis, abnormal pupillary light reflexes, a precipitous drop in intraocular pressure and loss of VMAT2-labelled (vesicle monoamine transporter-2, a marker for sympathetic neurones) intraocular neurones. Pre-treatment with Ap4A prevented all of these changes from being induced by 6-OHDA, demonstrably preserving the sympathetic innervation of the ciliary processes. This neuroprotective action of Ap4A was not shared with the related compounds adenosine, ATP or diadenosine pentaphosphate. P2-receptor antagonists showed that the effects of Ap4A were mediated via a P2-receptor. Conclusion:, Ap4A is a natural component of tears and aqueous humour, and its neuroprotective effect indicates that one of its physiological roles is to maintain neurones within the eye. Ap4A can prevent the degeneration of intraocular nerves, and it is suggested that this compound may provide the basis for a therapeutic intervention aimed at preventing or ameliorating the development of glaucoma associated with neurodegenerative diseases. Furthermore, subconjunctival application of 6-OHDA provides a useful model for studying diseases that cause ocular sympathetic dysautonomia. [source] Physiological functions of glucose-inhibited neuronesACTA PHYSIOLOGICA, Issue 1 2009D. Burdakov Abstract Glucose-inhibited neurones are an integral part of neurocircuits regulating cognitive arousal, body weight and vital adaptive behaviours. Their firing is directly suppressed by extracellular glucose through poorly understood signalling cascades culminating in opening of post-synaptic K+ or possibly Cl, channels. In mammalian brains, two groups of glucose-inhibited neurones are best understood at present: neurones of the hypothalamic arcuate nucleus (ARC) that express peptide transmitters NPY and agouti-related peptide (AgRP) and neurones of the lateral hypothalamus (LH) that express peptide transmitters orexins/hypocretins. The activity of ARC NPY/AgRP neurones promotes food intake and suppresses energy expenditure, and their destruction causes a severe reduction in food intake and body weight. The physiological actions of ARC NPY/AgRP cells are mediated by projections to numerous hypothalamic areas, as well as extrahypothalamic sites such as the thalamus and ventral tegmental area. Orexin/hypocretin neurones of the LH are critical for normal wakefulness, energy expenditure and reward-seeking, and their destruction causes narcolepsy. Orexin actions are mediated by highly widespread central projections to virtually all brain areas except the cerebellum, including monosynaptic innervation of the cerebral cortex and autonomic pre-ganglionic neurones. There, orexins act on two specific G-protein-coupled receptors generally linked to neuronal excitation. In addition to sensing physiological changes in sugar levels, the firing of both NPY/AgRP and orexin neurones is inhibited by the ,satiety' hormone leptin and stimulated by the ,hunger' hormone ghrelin. Glucose-inhibited neurones are thus well placed to coordinate diverse brain states and behaviours based on energy levels. [source] The physiology of rodent beta-cells in pancreas slicesACTA PHYSIOLOGICA, Issue 1 2009M. Rupnik Abstract Beta-cells in pancreatic islets form complex syncytia. Sufficient cell-to-cell electrical coupling seems to ensure coordinated depolarization pattern and insulin release that can be further modulated by rich innervation. The complex structure and coordinated action develop after birth during fast proliferation of the endocrine tissue. These emergent properties can be lost due to various reasons later in life and can lead to glucose intolerance and diabetes mellitus. Pancreas slice is a novel method of choice to study the physiology of beta-cells still embedded in their normal cellulo-social context. I present major advantages, list drawbacks and provide an overview on recent advances in our understanding of the physiology of beta-cells using the pancreas slice approach. [source] Clinical presentations of alopecia areataDERMATOLOGIC THERAPY, Issue 4 2001Maria K. Hordinsky Alopecia areata (AA) may can occur on any hair-bearing region. Patients can develop patchy nonscarring hair loss or extensive loss of all body hair. Hair loss may fluctuate. Some patients experience recurrent hair loss followed by hair regrowth, whereas others may only develop a single patch of hair loss, never to see the disease again. Still others experience extensive loss of body hair. The heterogeneity of clinical presentations has led investigators conducting clinical therapeutic trials to typically group patients into three major groups, those with extensive scalp hair loss [alopecia totalis (AT)], extensive body hair loss [alopecia universalis (AU)], or patchy disease (AA). Treatment outcomes have been correlated with disease duration and extent. Recently, guidelines were established for selecting and assessing subjects for both clinical and laboratory studies of AA, thereby facilitating collaboration, comparison of data, and the sharing of patient-derived tissue. For reporting purposes the terms AT and AU, though still used are defined very narrowly. AT is 100% terminal scalp hair loss without any body hair loss and AU is 100% terminal scalp hair and body loss. AT/AU is the term now recommended to define the presence of AT with variable amounts of body hair loss. In this report the term AA will be used broadly to encompass the many presentations of this disease. Development of AA may occur with changes in other ectodermal-derived structures such as fingernails and toenails. Some investigators have also suggested that other ectodermal-derived appendages as sebaceous glands and sweat glands may be affected in patients experiencing AA. Whether or not function of these glands is truly impaired remains to be confirmed. Many patients who develop patchy or extensive AA complain of changes in cutaneous sensation, that is, burning, itching, tingling, with the development of their disease. Similar symptoms may occur with hair regrowth. The potential involvement of the nervous system in AA has led to morphologic investigations of the peripheral nervous system as well as analysis of circulating neuropeptide levels. In this article the clinical presentations of AA are reviewed. The guidelines for conducting treatment studies of AA are presented and observations on changes in cutaneous innervation are introduced. Throughout the text, unless otherwise noted, AA will be used in a general way to denote the spectrum of this disease. [source] Id2, Id3, and Id4 proteins show dynamic changes in expression during vibrissae follicle developmentDEVELOPMENTAL DYNAMICS, Issue 6 2008Nigel L. Hammond Abstract Id proteins are involved in the transcriptional control of many fundamental biological processes, including differentiation and lineage commitment. We studied Id2, Id3, and Id4 protein expression during different stages of rat vibrissa follicle development using immunohistochemistry. Id2 was highly expressed in the cytoplasm of specialized cells in the basal epidermis and outer root sheath during early stages of follicle development. These cells were identified as Merkel cells (MCs) by means of double-immunolabeling with synaptophysin and cytokeratin-20, and persisted in neonatal follicles. Id3 immunofluorescence was characterized by membrane-associated expression in basal epithelial cells of follicles early in development. Subsequently follicle epithelial cells switched to have strong nuclear labeling, also a feature of newly forming dermal papilla cells. Id4 expression was primarily associated with innervation of the developing follicle musculature. These observations illustrate dynamic expression patterns of Id2 and Id3 proteins in developing follicles and specifically link Id2 expression to Merkel cell specification. Developmental Dynamics 237:1653,1661, 2008. © 2008 Wiley-Liss, Inc. [source] Foxg1 is required for morphogenesis and histogenesis of the mammalian inner earDEVELOPMENTAL DYNAMICS, Issue 9 2006Sarah Pauley Abstract The forkhead genes are involved in patterning, morphogenesis, cell fate determination, and proliferation. Several Fox genes (Foxi1, Foxg1) are expressed in the developing otocyst of both zebrafish and mammals. We show that Foxg1 is expressed in most cell types of the inner ear of the adult mouse and that Foxg1 mutants have both morphological and histological defects in the inner ear. These mice have a shortened cochlea with multiple rows of hair cells and supporting cells. Additionally, they demonstrate striking abnormalities in cochlear and vestibular innervation, including loss of all crista neurons and numerous fibers that overshoot the organ of Corti. Closer examination shows that some anterior crista fibers exist in late embryos. Tracing these fibers shows that they do not project to the brain but, instead, to the cochlea. Finally, these mice completely lack a horizontal crista, although a horizontal canal forms but comes off the anterior ampulla. Anterior and posterior cristae, ampullae, and canals are reduced to varying degrees, particularly in combination with Fgf10 heterozygosity. Compounding Fgf10 heterozygotic effects suggest an additive effect of Fgf10 on Foxg1, possibly mediated through bone morphogenetic protein regulation. We show that sensory epithelia formation and canal development are linked in the anterior and posterior canal systems. Much of the Foxg1 phenotype can be explained by the participation of the protein binding domain in the delta/notch/hes signaling pathway. Additional Foxg1 effects may be mediated by the forkhead DNA binding domain. Developmental Dynamics 235:2470,2482, 2006. © 2006 Wiley-Liss, Inc. [source] Development of otolith receptors in Japanese quailDEVELOPMENTAL NEUROBIOLOGY, Issue 6 2010David Huss Abstract This study examined the morphological development of the otolith vestibular receptors in quail. Here, we describe epithelial growth, hair cell density, stereocilia polarization, and afferent nerve innervation during development. The otolith maculae epithelial areas increased exponentially throughout embryonic development reaching asymptotic values near posthatch day P7. Increases in hair cell density were dependent upon macular location; striolar hair cells developed first followed by hair cells in extrastriola regions. Stereocilia polarization was initiated early, with defining reversal zones forming at E8. Less than half of all immature hair cells observed had nonpolarized internal kinocilia with the remaining exhibiting planar polarity. Immunohistochemistry and neural tracing techniques were employed to examine the shape and location of the striolar regions. Initial innervation of the maculae was by small fibers with terminal growth cones at E6, followed by collateral branches with apparent bouton terminals at E8. Calyceal terminal formation began at E10; however, no mature calyces were observed until E12, when all fibers appeared to be dimorphs. Calyx afferents innervating only Type I hair cells did not develop until E14. Finally, the topographic organization of afferent macular innervation in the adult quail utricle was quantified. Calyx and dimorph afferents were primarily confined to the striolar regions, while bouton fibers were located in the extrastriola and Type II band. Calyx fibers were the least complex, followed by dimorph units. Bouton fibers had large innervation fields, with arborous branches and many terminal boutons. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 436,455, 2010 [source] Phenotypic plasticity in number of glomeruli and sensory innervation of the antennal lobe in leaf-cutting ant workers (A. vollenweideri)DEVELOPMENTAL NEUROBIOLOGY, Issue 4 2010Christina Kelber Abstract In the leaf-cutting ant Atta vollenweideri, the worker caste exhibits a pronounced size-polymorphism, and division of labor is dependent on worker size (alloethism). Behavior is largely guided by olfaction, and the olfactory system is highly developed. In a recent study, two different phenotypes of the antennal lobe of Atta vollenweideri workers were found: MG- and RG-phenotype (with/without a macroglomerulus). Here we ask whether the glomerular numbers are related to worker size. We found that the antennal lobes of small workers contain ,390 glomeruli (low-number; LN-phenotype), and in large workers we found a substantially higher number of ,440 glomeruli (high-number; HN-phenotype). All LN-phenotype workers and some small HN-phenotype workers do not possess an MG (LN-RG-phenotype and HN-RG-phenotype), and the remaining majority of HN-phenotype workers do possess an MG (HN-MG-phenotype). Using mass-staining of antennal olfactory receptor neurons we found that the sensory tracts divide the antennal lobe into six clusters of glomeruli (T1,T6). In LN-phenotype workers, ,50 glomeruli are missing in the T4-cluster. Selective staining of single sensilla and their associated receptor neurons revealed that T4-glomeruli are innervated by receptor neurons from the main type of olfactory sensilla, the Sensilla trichodea curvata. The other type of olfactory sensilla (Sensilla basiconica) exclusively innervates T6-glomeruli. Quantitative analyses of differently sized workers revealed that the volume of T6 glomeruli scales with the power of 2.54 to the number of Sensilla basiconica. The results suggest that developmental plasticity leading to antennal-lobe phenotypes promotes differences in olfactory-guided behavior and may underlie task specialization within ant colonies. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 70: 222,234, 2010. [source] Activity of nAChRs containing ,9 subunits modulates synapse stabilization via bidirectional signaling programsDEVELOPMENTAL NEUROBIOLOGY, Issue 14 2009Vidya Murthy Abstract Although the synaptogenic program for cholinergic synapses of the neuromuscular junction is well known, little is known of the identity or dynamic expression patterns of proteins involved in non-neuromuscular nicotinic synapse development. We have previously demonstrated abnormal presynaptic terminal morphology following loss of nicotinic acetylcholine receptor (nAChR) ,9 subunit expression in adult cochleae. However, the molecular mechanisms underlying these changes have remained obscure. To better understand synapse formation and the role of cholinergic activity in the synaptogenesis of the inner ear, we exploit the nAChR ,9 subunit null mouse. In this mouse, functional acetylcholine (ACh) neurotransmission to the hair cells is completely silenced. Results demonstrate a premature, effusive innervation to the synaptic pole of the outer hair cells in ,9 null mice coinciding with delayed expression of cell adhesion proteins during the period of effusive contact. Collapse of the ectopic innervation coincides with an age-related hyperexpression pattern in the null mice. In addition, we document changes in expression of presynaptic vesicle recycling/trafficking machinery in the ,9 null mice that suggests a bidirectional information flow between the target of the neural innervation (the hair cells) and the presynaptic terminal that is modified by hair cell nAChR activity. Loss of nAChR activity may alter transcriptional activity, as CREB binding protein expression is decreased coincident with the increased expression of N-Cadherin in the adult ,9 null mice. Finally, by using mice expressing the nondesensitizing ,9 L9,T point mutant nAChR subunit, we show that increased nAChR activity drives synaptic hyperinnervation. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009 [source] Differential expression of TrkB isoforms switches climbing fiber-Purkinje cell synaptogenesis to selective synapse eliminationDEVELOPMENTAL NEUROBIOLOGY, Issue 10 2009Rachel M. Sherrard Abstract Correct neural function depends on precisely organized connectivity, which is refined from broader projections through synaptic/collateral elimination. In the rat, olivocerebellar topography is refined by regression of multiple climbing fiber (CF) innervation of Purkinje cells (PC) during the first two postnatal weeks. The molecules that initiate this regression are not fully understood. We assessed the role of cerebellar neurotrophins by examining tropomycin receptor kinase (Trk) receptor expression in the inferior olive and cerebellum between postnatal days (P)3-7, when CF-PC innervation changes from synapse formation to selective synapse elimination, and in a denervation-reinnervation model when synaptogenesis is delayed. Trks A, B, and C are expressed in olivary neurons; although TrkA was not transported to the cerebellum and TrkC was unchanged during innervation and reinnervation, suggesting that neither receptor is involved in CF-PC synaptogenesis. In contrast, both total and truncated TrkB (TrkB.T) increased in the olive and cerebellum from P4, whereas full-length and activated phosphorylated TrkB (phospho-TrkB) decreased from P4-5. This reveals less TrkB signaling at the onset of CF regression. This expression pattern was reproduced during CF-PC reinnervation: in the denervated hemicerebellum phospho-TrkB decreased as CF terminals degenerated, then increased in parallel with the delayed neosynaptogenesis as new CFs reinnervated the denervated hemicerebellum. In the absence of this signaling, CF reinnervation did not develop. Our data reveal that olivocerebellar TrkB activity parallels CF-PC synaptic formation and stabilization and is required for neosynaptogenesis. Furthermore, TrkB.T expression rises to reduce TrkB signaling and permit synapse elimination. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] Development and topography of the lateral olfactory tract in the mouse: Imaging by genetically encoded and injected fluorescent markersDEVELOPMENTAL NEUROBIOLOGY, Issue 8 2006Andreas Walz Abstract In mammals, conventional odorants are detected by OSNs located in the main olfactory epithelium of the nose. These neurons project their axons to glomeruli, which are specialized structures of neuropil in the olfactory bulb. Within glomeruli, axons synapse onto dendrites of projection neurons, the mitral and tufted (M/T) cells. Genetic approaches to visualize axons of OSNs expressing a given odorant receptor have proven very useful in elucidating the organization of these projections to the olfactory bulb. Much less is known about the development and connectivity of the lateral olfactory tract (LOT), which is formed by axons of M/T cells connecting the olfactory bulb to central neural regions. Here, we have extended our genetic approach to mark M/T cells of the main olfactory bulb and their axons in the mouse, by targeted insertion of IRES-tauGFP in the neurotensin locus. In NT-GFP mice, we find that M/T cells of the main olfactory bulb mature and project axons as early as embryonic day 11.5. Final innervation of central areas is accomplished before the end of the second postnatal week. M/T cell axons that originate from small defined areas within the main olfactory bulb, as visualized by localized injections of fluorescent tracers in wild-type mice at postnatal days 1 to 3, follow a dual trajectory: a branch of tightly packed axons along the dorsal aspect of the LOT, and a more diffuse branch along the ventral aspect. The dorsal, but not the ventral, subdivision of the LOT exhibits a topographical segregation of axons coming from the dorsal versus ventral main olfactory bulb. The NT-GFP mouse strain should prove useful in further studies of development and topography of the LOT, from E11.5 until 2 weeks after birth. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] Role of the neuropeptide CCAP in Drosophila cardiac functionDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2005Davide Dulcis Abstract The heartbeat of adult Drosophila melanogaster displays two cardiac phases, the anterograde and retrograde beat, which occur in cyclic alternation. Previous work demonstrated that the abdominal heart becomes segmentally innervated during metamorphosis by peripheral neurons that express crustacean cardioactive peptide (CCAP). CCAP has a cardioacceleratory effect when it is applied in vitro. The role of CCAP in adult cardiac function was studied in intact adult flies using targeted cell ablation and RNA interference (RNAi). Optical detection of heart activity showed that targeted ablation of CCAP neurons selectively altered the anterograde beat, without apparently altering the cyclic cardiac reversal. Normal development of the abdominal heart and of the remainder of cardiac innervation in flies lacking CCAP neurons was confirmed by immunocytochemistry. Thus, in addition to its important role in ecdysis behavior (the behavior used by insects to shed the remains of the old cuticle at the end of the molt), CCAP may control the level of activity of the anterograde cardiac pacemaker in the adult fly. Expression of double stranded CCAP RNA in the CCAP neurons (targeted CCAP RNAi) caused a significant reduction in CCAP expression. However, this reduction was not sufficient to compromise CCAP's function in ecdysis behavior and heartbeat regulation. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 [source] Myopodia (postsynaptic filopodia) participate in synaptic target recognitionDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2003Sarah Ritzenthaler Abstract Synaptic partner cells recognize one another by utilizing a variety of molecular cues. Prior to neuromuscular synapse formation, Drosophila embryonic muscles extend dynamic actin-based filopodia called "myopodia." In wild-type animals, myopodia are initially extended randomly from the muscle surface but become gradually restricted to the site of motoneuron innervation, a spatial redistribution we call "clustering." Previous experiments with prospero mutant embryos demonstrated that myopodia clustering does not occur in the absence of motoneuron outgrowth into the muscle field. However, whether myopodia clustering is due to a general signal from passing axons or is a result of the specific interactions between synaptic partners remained to be investigated. Here, we have examined the relationship of myopodia to the specific events of synaptic target recognition, the stable adhesion of synaptic partners. We manipulated the embryonic expression of ,PS2 integrin and Toll, molecules known to affect synaptic development, to specifically alter synaptic targeting on identified muscles. Then, we used a vital single-cell labeling approach to visualize the behavior of myopodia in these animals. We demonstrate a strong positive correlation between myopodia activity and synaptic target recognition. The frequency of myopodia clustering is lowered in cases where synaptic targeting is disrupted. Myopodia clustering seems to result from the adherence of a subset of myopodia to the innervating growth cone while the rest are eliminated. The data suggest that postsynaptic cells play a dynamic role in the process of synaptic target recognition. © 2003 Wiley Periodicals, Inc. J Neurobiol 55: 31,40, 2003 [source] | ||||||||||||||||||||||||||||||||||