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Peripheral Organs (peripheral + organ)
Selected AbstractsSynergistic regulation of neuropeptide levels by internal and external stimuliEXPERIMENTAL DERMATOLOGY, Issue 9 2004J. Hosoi The skin is the most peripheral organ confronting the external environment. We found that the level of substance P is regulated by both internal and external stimuli. Mock interview induced the acute stress in human assessed by the measurement of serum cortisol. The serum level of substance P increased within 1 h after the mock interview. Interestingly, the increase was suppressed by inhalation of 1,3-dimethoxy-5-methylbenzene. Similar regulation was observed in mice. Furthermore, restraint or the intravenous administration of substance P induced the activation of cutaneous mast cells. Housing under the condition of lower humidity (about 30%) for 24 h caused the increase in the substance P level both in peripheral blood and in the skin. Restraint for 2 h during the housing under the condition of lower humidity increased the substance P level further. The activation of cutaneous mast cells under the dry condition was reported. These data suggest that cutaneous neuropeptide level is regulated by both psychological and environmental mechanisms. The regulation may cause the downregulation of the threshold of the induction of itch and inflammation. [source] Frequency and Localization of the Putative Vomeronasal Organ in Humans in Relation to Age and Gender,THE LARYNGOSCOPE, Issue 3 2001Michael Knecht MD Abstract Objectives/Hypotheses In many species the vomeronasal organ (VNO) serves as a chemosensory organ in addition to the olfactory system. The present investigation was undertaken to study 1) the frequency of monolateral or bilateral detection of the putative VNO (pVNO) in humans, 2) its localization in humans, and 3) whether detectability of the pVNO varies with age or gender. Study Design Prospective. Methods A total of 173 subjects participated in this study (88 women and 85 men; age range, 2,91 y). Inspection of the nose was performed with a speculum and a 30° endoscope. The exact localization of the VNO was measured with custom-built rulers. Results The study revealed the following major results: 1) A pVNO is detectable in approximately two-thirds of the population and bilateral pVNOs are present in approximately 40% of investigated subjects, 2) its localization on the left and right nasal septum is almost symmetrical, and 3) and detectability of the pVNO is not related to age or gender. Conclusions The present data indicated that the pVNO is present in approximately two-thirds of the population. This value may be biased by methodological or biological factors; nevertheless, it indicates that the pVNO is not observed in all humans regardless of age and gender. Thus, considering its variability in shape and immunohistochemical characteristics and the missing nerval connections between the peripheral "organ" and the central nervous system, the present results are not suited to argue for a functional significance of the pVNO in humans. [source] Chronic inhibition of standing behaviour alters baroreceptor reflex function in ratsACTA PHYSIOLOGICA, Issue 3 2009H. Waki Abstract Aim:, To investigate whether daily orthostatic stress during development is an important factor affecting arterial baroreceptor reflex function, we examined the effect of chronic inhibition of upright standing behaviour on the baroreceptor reflex function in rats. Methods:, Upright standing behaviour was chronically inhibited during the developmental period between 3 and 8 weeks of age in Sprague,Dawley rats and heart rate (HR) and aortic nerve activity in response to increased and decreased mean arterial pressure (MAP) was measured after the treatment period. Results:, The baroreceptor cardiac gain in the rats grown without standing behaviour was significantly lower than the control rats grown in a normal commercial cage (1.0 ± 0.1 beats min,1 mmHg,1 vs. 1.6 ± 0.2 beatsmin,1 mmHg,1, P < 0.05). The range of HR change in the MAP,HR functional curve was also lowered by chronic inhibition of orthostatic behaviour (56.2 ± 5.9 beats min,1) compared with that of the control rats (76.8 ± 6.9 beats min,1, P < 0.05). However the aortic afferent function remained normal after the treatment period, indicating that the attenuated baroreceptor reflex function may be due to other mechanisms involving functional alterations in the cardiovascular centres, efferents and/or peripheral organs. Body weight and adrenal weight were not affected by the inhibition of orthostatic behaviour, suggesting that the animals were not exposed to specific stress by this treatment. Conclusion:, These results indicate that active haemodynamic changes induced by orthostatic behaviour are an important factor for setting the basal level of reflex function during development. Moreover, our experimental model may be useful for studying mechanisms of attenuated baroreceptor reflex observed after exposure to a chronic inactive condition. [source] Generalized multi-organ autoimmunity in CCR7-deficient miceEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2007Abstract Development of autoimmunity is a multi-factorial process involving genetic predisposition as well as environmental and stochastic factors. Although the mechanisms responsible for the initiation of autoimmunity remain only partially understood, several studies have demonstrated that genetic predisposition plays a major role in this process. In the present study, we analyzed the influence of CCR7 signaling in the development of autoimmunity, because this chemokine receptor is essentially involved in the functional organization of thymus architecture. We demonstrate that CCR7-deficient mice are prone to develop generalized multi-organ autoimmunity. The autoimmune phenotype of CCR7,/, mice encompasses the presence of lymphocyte infiltrates in several peripheral organs, circulating autoantibodies against a multitude of tissue-specific antigens and IgG deposition on renal glomeruli. Additionally, CCR7-deficient mice show increased susceptibility to streptozotocin-induced diabetes and spontaneously display signs of chronic autoimmune renal disease. Thus, this study identifies CCR7 as a genetic factor involved in the regulation of autoimmunity. [source] Role of exercise-induced brain-derived neurotrophic factor production in the regulation of energy homeostasis in mammalsEXPERIMENTAL PHYSIOLOGY, Issue 12 2009Bente K. Pedersen Brain-derived neurotrophic factor (BDNF) has been shown to regulate neuronal development and plasticity and plays a role in learning and memory. Moreover, it is well established that BDNF plays a role in the hypothalamic pathway that controls body weight and energy homeostasis. Recent evidence identifies BDNF as a player not only in central metabolism, but also in regulating energy metabolism in peripheral organs. Low levels of BDNF are found in patients with neurodegenerative diseases, including Alzheimer's disease and major depression. In addition, BDNF levels are low in obesity and independently so in patients with type 2 diabetes. Brain-derived neurotrophic factor is expressed in non-neurogenic tissues, including skeletal muscle, and exercise increases BDNF levels not only in the brain and in plasma, but in skeletal muscle as well. Brain-derived neurotrophic factor mRNA and protein expression was increased in muscle cells that were electrically stimulated, and BDNF increased phosphorylation of AMP-activated protein kinase (AMPK) and acetyl coenzyme A carboxylase-beta (ACC,) and enhanced fatty oxidation both in vitro and ex vivo. These data identify BDNF as a contraction-inducible protein in skeletal muscle that is capable of enhancing lipid oxidation in skeletal muscle via activation of AMPK. Thus, BDNF appears to play a role both in neurobiology and in central as well as peripheral metabolism. The finding of low BDNF levels both in neurodegenerative diseases and in type 2 diabetes may explain the clustering of these diseases. Brain-derived neurotrophic factor is likely to mediate some of the beneficial effects of exercise with regard to protection against dementia and type 2 diabetes. [source] Bioluminescence imaging allows measuring CD8 T cell function in the liver,HEPATOLOGY, Issue 4 2010Dirk Stabenow In vivo evaluation of CD8 T cell effector (cytotoxic T lymphocyte [CTL]) function in peripheral organs such as the liver is currently not possible but would greatly improve our understanding of local immune regulation, because simple determination of antigen-specific CTL numbers does not predict the outcome of immune responses. In particular, measurement of alanine aminotransferase serum levels is not sensitive enough to detect T cell immunity against low numbers of target hepatocytes. We developed a procedure that detects virus-specific effector function of CTLs in the liver after simultaneous adenoviral transfer of reporter and immune target genes into hepatocytes, followed by bioluminescence imaging of reporter genes. Bioluminescence imaging enabled detection of as few as 10,000 infected hepatocytes in vivo, and even more importantly, quantification of antiviral effector function of as few as 50,000 CTLs. Conclusion: Our results provide evidence that low numbers of antigen-specific CTLs are sufficient to control viral gene expression and eliminate viral infection from hepatocytes. The experimental system established here is a highly sensitive method to simultaneously detect viral infection of hepatocytes and to quantify antiviral CTL function in the liver in vivo and will help in characterizing principles of hepatic immune regulation. (HEPATOLOGY 2010;51:1430,1437) [source] Endotoxin translocation in two models of experimental acute pancreatitisJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2003C. Vasilescu Abstract To test the hypothesis that endotoxin is absorbed from the gut into the circulation in rats with experimental acute pancreatitis we studied two different animal models. In the first model necrotizing pancreatitis was induced by the ligation of the disatl bilio-pancreatic duct while in the second, experimental oedematous acute pancreatitis was induced by subcutaneous injections of caerulein. In both experiments, in the colon of rats with acute pancreatitis endotoxin from Salmonella abortus equi was injected. Endotoxin was detected by immunohistochemistry in peripheral organs with specific antibodies. The endotoxin was found only in rats with both acute pancreatitis and endotoxin injected into the colon and not in the control groups. The distribution of endotoxin in liver at 3 and 5 days was predominantly at hepatocytes level around terminal hepatic venules, while in lung a scattered diffuse pattern at the level of alveolar macrophages was identified. A positive staining was observed after 12 hours in the liver, lung, colon and mesenteric lymph nodes of rats with both caerulein pancreatitis and endotoxin injected into the colon. We conclude that the experimental acute pancreatitis leads to early endotoxin translocation from the gut lumen in the intestinal wall and consequent access of gut-derived endotoxin to the mesenteric lymph nodes, liver and lung. [source] Characterization of CD8-positive macrophages infiltrating the central nervous system of rats with chronic autoimmune encephalomyelitisJOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2009Keiko Hiraki Abstract CD8+ macrophages appear in the central nervous system (CNS) under various pathological conditions such as trauma and ischemia. Furthermore, macrophages expressing CD8 were found in CNS lesions of chronic, but not acute, experimental autoimmune encephalomyelitis (EAE). To further characterize cells with this phenotype, we examined CD8+ macrophages/monocytes in the CNS and peripheral organs during the course of acute and chronic EAE that had been induced by immunization of rats with myelin basic protein and myelin oligodendrocyte glycoprotein, respectively. Counting CD8+ macrophages in CNS lesions revealed that their numbers increased reaching about 60% of total infiltrating macrophages in chronic EAE, while CD8+ macrophages remained less than 5% throughout the course of acute EAE. Unexpectedly, however, higher abundance of CD8+ monocytes/macrophages in the peripheral blood was found in both acute and chronic EAE. Real-time polymerase chain reaction analysis revealed no significant difference in the levels of chemokines and chemokine receptors of blood CD8+ monocytes between acute and chronic EAE. mRNA expression of perforin, a cytotoxic substance, was up-regulated in CD8+ monocytes compared with that of CD8, monocytes in both acute and chronic EAE. These findings suggest that activated CD8+ macrophages may play a cytotoxic role in chronic EAE lesions and that cells other than CD8+ monocytes/macrophages determined the difference in CNS pathology between acute and chronic EAE. Analysis of CD8+ monocytes/macrophages may provide useful information to permit further dissect the pathomechanisms of multiple sclerosis and to develop effective immunotherapies against autoimmune diseases in the CNS. © 2008 Wiley-Liss, Inc. [source] Role of TPH-2 in brain function: News from behavioral and pharmacologic studiesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 14 2007Roberto W. Invernizzi Abstract The recent discovery of TPH-2, a new isoform of tryptophan hydroxylase, the enzyme that catalyses the transformation of tryptophan into 5-hydroxytryptophan and the rate-limiting step in brain serotonin (5-HT) biosynthesis, has boosted new interest in the many functions of 5-HT in the brain and non-nervous tissues. Recent studies on TPH-2 are reviewed with particular attention to the role of this enzyme in behavior and in response to drugs as assessed by comparing strains of mice carrying a functional polymorphism of TPH-2. Most studies concur to indicate that 5-HT synthesis through TPH-2 influence nervous tissues whereas TPH-1 is responsible for the synthesis and action of 5-HT in peripheral organs. Partial impairment of brain 5-HT synthesis caused by polymorphism of the gene encoding TPH-2 causes reduced release of the neurotransmitter, increased aggressiveness, and alters the response to drugs inhibiting the reuptake of 5-HT. Strain comparison might be a useful strategy to investigate the genotype-dependent alterations of TPH-2. © 2007 Wiley-Liss, Inc. [source] Moonlight affects nocturnal Period2 transcript levels in the pineal gland of the reef fish Siganus guttatusJOURNAL OF PINEAL RESEARCH, Issue 2 2008Nozomi Sugama Abstract:, The golden rabbitfish Siganus guttatus is a reef fish with a restricted lunar-synchronized spawning cycle. It is not known how the fish recognizes cues from the moon and exerts moon-related activities. In order to evaluate the perception and utilization of moonlight by the fish, the present study aimed to clone and characterize Period2 (Per2), a light-inducible clock gene in lower vertebrates, and to examine daily variations in rabbitfish Per2 (rfPer2) expression as well as the effect of light and moonlight on its expression in the pineal gland. The partially-cloned rfPer2 cDNA (2933 bp) was highly homologous (72%) to zebrafish Per2. The rfPer2 levels increased at ZT6 and decreased at ZT18 in the whole brain and several peripheral organs. The rfPer2 expression in the pineal gland exhibited a daily variation with an increase during daytime. Exposing the fish to light during nighttime resulted in a rapid increase of its expression in the pineal gland, while the level was decreased by intercepting light during daytime. Two hours after exposing the fish to moonlight at the full moon period, the rfPer2 expression was upregulated. These results suggest that rfPer2 is a light-inducible clock gene and that its expression is affected not only by daylight but also by moonlight. Since the rfPer2 expression level during the full moon period was higher than that during the new moon period, the monthly variation in the rfPer2 expression is likely to occur with the change in amplitude between the full and new moon periods. [source] Pituitary adenylate cyclase-activating polypeptide and its receptors in amphibiansMICROSCOPY RESEARCH AND TECHNIQUE, Issue 3 2001Laurent Yon Abstract Pituitary adenylate cyclase-activating polypeptide (PACAP), a novel peptide of the secretin/glucagon/vasoactive intestinal polypeptide superfamily, has been initially characterized in mammals in 1989 and, only 2 years later, its counterpart has been isolated in amphibians. A number of studies conducted in the frog Rana ridibunda have demonstrated that PACAP is widely distributed in the central nervous system (particularly in the hypothalamus and the median eminence) and in peripheral organs including the adrenal gland. The cDNAs encoding the PACAP precursor and 3 types of PACAP receptors have been cloned in amphibians and their distribution has been determined by in situ hybridization histochemistry. Ontogenetic studies have revealed that PACAP is expresssed early in the brain of tadpoles, soon after hatching. In the frog Rana ridibunda, PACAP exerts a large array of biological effects in the brain, pituitary, adrenal gland, and ovary, suggesting that, in amphibians as in mammals, PACAP may act as neurotrophic factor, a neurotransmitter and a neurohormone. Microsc. Res. Tech. 54:137,157, 2001. © 2001 Wiley-Liss, Inc. [source] Localization of putative nitrergic neurons in peripheral chemosensory areas and the central nervous system of Aplysia californicaTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2006Leonid L. Moroz Abstract The distribution of putative nitric oxide synthase (NOS)-containing cells in the opisthobranch mollusc Aplysia californica was studied by using NADPH-diaphorase (NADPH-d) histochemistry in the CNS and peripheral organs. Chemosensory areas (the mouth area, rhinophores, and tentacles) express the most intense staining, primarily in the form of peripheral highly packed neuropil regions with a glomerular appearance as well as in epithelial sensory-like cells. These epithelial NADPH-d-reactive cells were small and had multiple apical ciliated processes exposed to the environment. NADPH-d processes were also found in the salivary glands, but there was no or very little staining in the buccal mass and foot musculature. In the CNS, most NADPH-d reactivity was associated with the neuropil of the cerebral ganglia, with the highest density of glomeruli-like NADPH-d-reactive neurites in the areas of the termini and around F and C clusters. A few NADPH-d-reactive neurons were also found in other central ganglia, including paired neurons in the buccal, pedal, and pleural ganglia and a few asymmetrical neurons in the abdominal ganglion. The distribution patterns of NADPH-d-reactive neurons did not overlap with other known neurotransmitter systems. The highly selective NADPH-d labeling revealed here suggests the presence of NOS in sensory areas both in the CNS and the peripheral organs of Aplysia and implies a role for NO as a modulator of chemosensory processing. J. Comp. Neurol. 495:10,20, 2006. © 2006 Wiley-Liss, Inc. [source] Chromosomal assignments for porcine genes encoding enzymes in hepatic metabolic pathwaysANIMAL GENETICS, Issue 4 2002K. Wimmers Increasing the number of mapped genes will facilitate (1) the identification of potential candidate genes for a trait of interest within quantitative trait loci regions and (2) comparative mapping. The metabolic activities of the liver are essential for providing fuel to peripheral organs, for regulation of amino acid, carbohydrate and lipid metabolism and for homoeostasis of vitamins, minerals and electrolytes. We aimed to identify and map genes coding for enzymes active in the liver by somatic cell genetics in order to contribute to the improvement of the porcine gene map. We mapped 28 genes of hepatic metabolic pathways including six genes whose locations could be confirmed and 22 new assignments. Localization information in human was available for all but one gene. In total 24 genes were assigned to in the expected chromosomal regions on the basis of the currently available information on the comparative human and pig map while for four genes our results suggest a new correspondence or extended regions of conservation between porcine and human chromosomes. [source] How Palatable Food Disrupts Appetite RegulationBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2005Charlotte Erlanson-Albertsson Hunger signals may be generated in peripheral organs (e.g. ghrelin) but most of them are expressed in the hypothalamus (neuropeptide Y, orexins, agouti-related peptide, melanin concentrating hormone, endogenous opiates and dopamine) and are expressed during situations of energy deficiency. Some satiety signals, such as cholecystokinin, glucagon-like peptide 1, peptide YY and enterostatin are released from the digestive tract in response to food intake. Others, such as leptin and insulin, are mobilized in response to perturbations in the nutritional state. Still others are generated in neurones of the hypothalamus (,-melanocyte-stimulating hormone and serotonin). Satiety signals act by inhibiting the expression of hunger signals and/or by blunting their effect. Palatable food, i.e. food rich in fat and sugar, up-regulates the expression of hunger signals and satiety signals, at the same time blunting the response to satiety signals and activating the reward system. Hence, palatable food offsets normal appetite regulation, which may explain the increasing problem of obesity worldwide. [source] Monoamine oxidase A and B activities in embryonic chick hepatocytes: differential regulation by retinoic acidCELL BIOCHEMISTRY AND FUNCTION, Issue 2 2002Antonietta Nicotra Abstract Monoamine oxidases (MAOs) A and B are two isoenzymes involved in the degradation of many biological amines in the nervous system and in peripheral organs. In the present work hepatocytes isolated from 14-day-old chick embryos were used as a model system to determine whether retinoic acid (RA) is capable of modulating the activity of the two MAO forms. RA is a retinoid that, by binding with nuclear receptors, interferes with the expression of specific genes in many differentiation processes. Enzymic activity was measured with a radiochemical method using serotonin and ,-phenylethylamine as preferential substrates for MAO A and MAO B, respectively. The specific activity of the two forms was measured in hepatocytes cultured for 24, 48 and 72,h in the presence and the absence of serum. RA stimulated MAO B but not MAO A activity, in a dose- and time-dependent way, and only in the presence of serum. Maximum stimulation (about 3.5-fold) was obtained after treatment with 5,,M RA for 72,h. Kinetic analysis of MAO B activity showed an increase in Vmax in treated hepatocytes (5,,M RA for 72,h) with no change in Km. In conclusion, the present work shows that RA selectively elicits MAO B activity in cultured chick embryonic hepatocytes, this stimulation requires the presence of some factors present in the serum and is probably due to an increase in the number of enzyme molecules. Copyright © 2001 John Wiley & Sons, Ltd. [source] | |||||||||||||