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Immunoreactive Nerve Fibers (immunoreactive + nerve_fiber)
Selected AbstractsDemonstration of an orexinergic central innervation of the pineal gland of the pigTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 2 2004Chiara Fabris Abstract Orexins/hypocretins, two isoforms of the same prepropeptide, are widely distributed throughout the brain and are involved in several physiological and neuroendocrine regulatory patterns, mostly related to feeding, sleep, arousal, and cyclic sleep-wake behaviors. Orexin-A and orexin-B bind with different affinities to two G-protein-coupled transmembrane receptors, orexin-1 and orexin-2 receptors (OR-R1 and OR-R2, respectively). Because of the similarities between the human and the swine brain, we have studied the pig to investigate the orexinergic system in the diencephalon, with special emphasis on the neuroanatomical projections to the epithalamic region. By using antibodies against orexin-A and orexin-B, immunoreactive large multipolar perikarya were detected in the hypothalamic periventricular and perifornical areas at the light and electron microscopic levels. In the region of the paraventricular nucleus, the orexinergic neurons extended all the way to the lateral hypothalamic area. Immunoreactive nerve fibers, often endowed with large varicosities, were found throughout the hypothalamus and the epithalamus. Some periventricular immunoreactive nerve fibers entered the epithalamic region and continued into the pineal stalk and parenchyma to disperse among the pinealocytes. Immunoelectron microscopy confirmed the presence of orexinergic nerve fibers in the pig pineal gland. After extraction of total mRNA from the hypothalamus and pineal gland, we performed RT-PCR and nested PCR using primers specific for porcine orexin receptors. PCR products were sequenced, verifying the presence of both OR-R1 and OR-R2 in the tissues investigated. These findings, supported by previous studies on rodents, suggest a hypothalamic regulation of the pineal gland via central orexinergic nervous inputs. J. Comp. Neurol. 471:113,127, 2004. © 2004 Wiley-Liss, Inc. [source] Immunohistochemical Characterization of Neurones in the Hypoglossal Nucleus of the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2010W. Sienkiewicz Summary With 4 figures and 1 table In this study, the presence of several neurotransmitters and transmitter synthesizing enzymes was studied in hypoglossal nucleus (HN) of the juvenile (4 months old) female pigs (n = 3). Double-labeling immunofluorescence revealed neurones expressing cholinacetyltranspherase (ChAT), calcitonin gene-related peptide (CGRP), nitric oxide synthase (NOS), and somatostatin (SOM). Nerve fibers within HN were ChAT, CGRP, NOS, SOM, substance P (SP), Leu-5-enkephalin (Leu-5-Enk), ß-dopamine hydroxylase (DßH), neuropeptide Y (NPY) positive. Virtually all the perikarya contained ChAT, whereas CGRP was present in 47% of the neurones. Nerve cell bodies containing NOS or SOM were only occasionally observed. Immunoreactive nerve fibers were found in a close vicinity of the perikarya, often forming baskets around nerve cell bodies. The results obtained were compared with similar data obtained in other species. The presence of immunoreactive structures, origin of the nerve fibers, and functional significance of the findings are discussed. [source] Innervation pattern and Ca2+ signalling in labial salivary glands of healthy individuals and patients with primary Sjögren's syndrome (pSS)JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 3 2000Anne Marie Pedersen Abstract: We have characterised the innervation pattern and intracellular Ca2+ -signalling in labial salivary glands (LSG) of 16 patients with primary Sjögren's syndrome (pSS) and 27 healthy controls. Numerous immunoreactive nerve fibers (IRF) containing vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating peptide (PACAP) were found around acini, ducts and blood vessels. Substance P (SP)-, neuropeptide Y-, tyrosine hydroxylase- and nitric oxide synthase-IRF were mainly surrounding ducts and blood vessels. The majority of pSS patients had inflamed LSG and the presence of focal lymphocytic infiltrates (FI) were more frequent and pronounced as compared with healthy controls. In areas with normal or diffusely inflamed LSG tissue, pSS patients demonstrated the same distribution of IRF as healthy controls with similar histology. However, IRF were absent in central areas of FI both in pSS and age-matched healthy controls. Although all pSS patients had hyposalivation, stimulation with acetylcholine, norepinephrine, phenylephrine, isoproterenol, VIP, PACAP, SP, adenosine 5,-triphosphate and uridine 5,-triphosphate induced the same increase in the intracellular free Ca2+ concentration in LSG acini from both pSS patients and healthy controls, indicating the presence of functional receptor systems in vitro. [source] Evidence for target-specific outgrowth from subpopulations of grafted human dopamine neuronsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 5 2001Ingrid Strömberg Abstract Clinical and experimental grafting in Parkinson's disease has shown the need for enhanced survival of dopamine neurons to obtain improved functional recovery. In addition, it has been suggested that a limited number of surviving dopamine neurons project to the dopamine-denervated host striatum. The aim of this study was to investigate if subpopulations of ventral mesencephalic dopamine neurons project to their normal targets, i.e., dorsal vs. ventral striatum. Following implantation of human ventral mesencepahlic tissue into the lateral ventricle of dopamine-depleted rats, human-derived dopamine reinnervation was achieved both in dorsal and ventral striatum. Treatment with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) resulted in a degeneration of tyrosine hydroxylase (TH)-immunoreactive nerve fibers in dorsal striatum but not in ventral areas in some animals, while MPTP was without effect in other animals. TH-immunoreactive neurons were small and appeared shrunken in animals carrying grafts affected by the MPTP treatment. In conclusion, grafted dopamine neurons projected nerve fibers into areas that they normally innervate. Thus, when searching for factors that may enhance survival of grafted dopamine neurons it is important to study which subpopulation(s) of ventral mesencephalic dopamine neurons is affected, such that a proper reinnervation may be achieved. Microsc. Res. Tech. 54:287,297, 2001. © 2001 Wiley-Liss, Inc. [source] Functional immunohistochemistry of neuropeptides and nitric oxide synthase in the nerve fibers of the supratentorial dura mater in an experimental migraine modelMICROSCOPY RESEARCH AND TECHNIQUE, Issue 3 2001Elizabeth Knyihár-Csillik Abstract The supratentorial cerebral dura of the albino rat is equipped with a rich sensory innervation both in the connective tissue and around blood vessels, which includes nociceptive axons and their terminals; these display intense calcitonin gene-related peptide (CGRP) immunoreactivity. Stereotactic electrical stimulation of the trigeminal (Gasserian) ganglion, regarded as an experimental migraine model, caused marked increase and disintegration of club-like perivascular CGRP-immunopositive nerve endings in the dura mater and induced an apparent increase in the lengths of CGRP-immunoreactive axons. Intravenous administration of sumatriptan or eletriptan, prior to electrical stimulation, prevented disintegration of perivascular terminals and induced accumulation of CGRP in terminal and preterminal portions of peripheral sensory axons. Consequently, immunopositive terminals and varicosities increased in size; accumulation of axoplasmic organelles resulted in the "hollow" appearence of numerous varicosities. Since triptans exert their anti-migraine effect by virtue of agonist action on 5-HT1D/B receptors, we suggest that these drugs prevent the release of CGRP from perivascular nerve terminals in the dura mater by an action at 5-HT1D/B receptors. Nitroglycerine (NitroPOHL), given subcutaneously to rats, induces increased beading of nitric oxide synthase (NOS)-immunoreactive nerve fibers in the supratentorial cerebral dura mater, and an apparent increase in the number of NOS-immunoreactive nerve fibers in the dural areas supplied by the anterior and middle meningeal arteries, and the sinus sagittalis superior. Structural alterations of nitroxidergic axons innervating blood vessels of the dura mater support the idea that nitric oxide (NO) is involved in the induction of headache, a well-known side effect of coronary dilator agents. Microsc. Res. Tech. 53:193,211, 2001. © 2001 Wiley-Liss, Inc. [source] Demonstration of an orexinergic central innervation of the pineal gland of the pigTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 2 2004Chiara Fabris Abstract Orexins/hypocretins, two isoforms of the same prepropeptide, are widely distributed throughout the brain and are involved in several physiological and neuroendocrine regulatory patterns, mostly related to feeding, sleep, arousal, and cyclic sleep-wake behaviors. Orexin-A and orexin-B bind with different affinities to two G-protein-coupled transmembrane receptors, orexin-1 and orexin-2 receptors (OR-R1 and OR-R2, respectively). Because of the similarities between the human and the swine brain, we have studied the pig to investigate the orexinergic system in the diencephalon, with special emphasis on the neuroanatomical projections to the epithalamic region. By using antibodies against orexin-A and orexin-B, immunoreactive large multipolar perikarya were detected in the hypothalamic periventricular and perifornical areas at the light and electron microscopic levels. In the region of the paraventricular nucleus, the orexinergic neurons extended all the way to the lateral hypothalamic area. Immunoreactive nerve fibers, often endowed with large varicosities, were found throughout the hypothalamus and the epithalamus. Some periventricular immunoreactive nerve fibers entered the epithalamic region and continued into the pineal stalk and parenchyma to disperse among the pinealocytes. Immunoelectron microscopy confirmed the presence of orexinergic nerve fibers in the pig pineal gland. After extraction of total mRNA from the hypothalamus and pineal gland, we performed RT-PCR and nested PCR using primers specific for porcine orexin receptors. PCR products were sequenced, verifying the presence of both OR-R1 and OR-R2 in the tissues investigated. These findings, supported by previous studies on rodents, suggest a hypothalamic regulation of the pineal gland via central orexinergic nervous inputs. J. Comp. Neurol. 471:113,127, 2004. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||