Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using in situ hybridization histochemistry, we have investigated the effect of thyroid hormone on the expression of several peptide mRNAs in the hypothalamic paraventricular nucleus (PVN) of adult male rats. Hypothyroidism was induced by surgical ablation of the thyroid gland. The animals (control sham-operated, thyroidectomized, thyroidectomized+T4 replaced rats) were studied 28 and 50 days after surgery. Sections of the PVN were hybridized using synthetic oligonucleotide probes complementary to mRNA for thyrotropin-releasing hormone (TRH), corticotropin-releasing hormone (CRH), galanin (GAL), enkephalin (ENK), neurotensin (NT), vasoactive intestinal polypeptide (VIP) and vasopressin (VP). GAL mRNA was also analyzed in the anterior paraventricular, arcuate, and dorsomedial nuclei of the hypothalamus. At the PVN level, a feedback effect of thyroid hormone on TRH synthesis was demonstrated by the TRH mRNA increase in hypothyroidism and by its decrease in hyperthyroidism. Hypothyroidism caused a dramatic decrease in GAL mRNA in parvo- and magnocellular PVN neurons both 28 and 50 days after thyroid ablation, whereas no effect was seen in VP mRNA, the main peptide hormone coexisting with GAL. The T4 replacement prevented the GAL mRNA impairment. Hypothyroidism did not influence GAL mRNA in the anterior PVN, perifornical area or in the arcuate nucleus, whereas a decrease in GAL mRNA was observed in the dorsomedial nucleus. VIP mRNA, which is undetectable in the PVN of normal animals, was present in several PVN neurons after thyroidectomy. CRH mRNA was decreased after thyroidectomy, whereas the T4 restitution caused an upregulation. The levels of ENK or NT mRNA were not significantly affected by the thyroid status. The present results show that, in addition to TRH mRNA, other hypothalamic peptide mRNAs are affected by thyroid hormone levels.
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PMID:Response of hypothalamic peptide mRNAs to thyroidectomy. 128 6

Tuberomammillary neurons in the posterior hypothalamus are the sole source of neuronal histamine in adult mammalian brain. In the rat, these cells are reported to contain immunoreactivity for gamma-aminobutyric acid (GABA) and several neuropeptides. We compared the presence of these substances in the tuberomammillary cells of the rat, mouse, and guinea pig. In all three species, all histamine-immunoreactive neuronal cell bodies were positive for GABA. This suggests that GABAergic transmission may be important in tuberomammillary function. No cell bodies immunoreactive for thyrotropin releasing hormone (TRH) were found in the guinea pig or mouse tuberomammillary area. In contrast, about 14% of the histamine-immunoreactive tuberomammillary cells in the rat were TRH-positive. These cells were small or medium-sized and were located only in the medial part of the tuberomammillary complex. An antibody against porcine galanin stained about 45% of the tuberomammillary cell bodies in the rat and about 28% in the mouse, but none in the guinea pig. A large proportion of the cells in the rat and mouse, but none in the guinea pig, were positive for met-enkephalin-arg-phe. In contrast, all histamine-containing tuberomammillary cells in the guinea pig, but none in the rat or mouse, were immunoreactive for met-enkephalin. This may indicate a different expression of proenkephalin-derived peptides in the tuberomammillary neurons in these species. Some substance P-immunoreactive cell bodies were located in the tuberomammillary area in all three species. However, only 3% of the histamine-immunoreactive cell bodies in the rat and mouse but none in the guinea pig were substance P-positive. The neurochemical properties of the tuberomammillary nucleus that exhibited species commonality deserve to be studied neurochemically and electrophysiologically in order to determine the functional relevance of coexisting transmitters in this nucleus.
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PMID:Multiple neurotransmitters in the tuberomammillary nucleus: comparison of rat, mouse, and guinea pig. 138 90

The topographical distribution of neuropeptide-containing cell bodies, fibers and terminals was studied in human parabrachial nuclei and the pontine tegmentum with immunohistochemical stainings. Brains of seven adult human subjects of 35-72 years were fixed within 2 h post mortem. Serial sections were immunostained by antisera of 14 different neuropeptides--oxytocin, vasopressin, thyrotropin-releasing hormone, angiotensin II, calcitonin gene-related peptide, beta-endorphin, dynorphin A, dynorphin B, leucine-enkephalin, alpha-melanocyte stimulating hormone, substance P, neuropeptide Y, cholecystokinin and galanin--alternately. All of these peptides were found to be present in nerve fibers and terminals, but only two, angiotensin II and dynorphin B, in cell bodies of the parabrachial nuclei. Calcitonin gene-related peptide-, neuropeptide Y-, cholecystokinin- and galanin-immunoreactive cells were present in other areas of the pontine tegmentum, like the motor trigeminal nucleus, locus coeruleus, periventricular gray matter but not in the parabrachial nuclei. Peptidergic fibers were distributed unevenly throughout the pontine tegmentum having unique, individual distribution patterns. In the parabrachial nuclei, substance P, neuropeptide Y, cholecystokinin and galanin showed the highest density of immunoreactive neuronal networks. Moderate to low concentrations of immunoreactive processes were detected by calcitonin gene-related peptide, alpha-melanocyte stimulating hormone, dynorphin B, thyrotropin releasing hormone, leucine-enkephalin, dynorphin A, angiotensin II, beta-endorphin, vasopressin and oxytocin antisera, respectively. Other pontine tegmental areas, like the locus coeruleus, dorsal tegmental, pontine raphe and motor trigeminal nuclei as well as the central gray of the tegmental region exhibited a varying assortment of neuropeptides with distinct, individual localization patterns. Their detailed topographical distributions are mapped and given in coronal sections.
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PMID:Immunohistochemical study on the distribution of neuropeptides within the pontine tegmentum--particularly the parabrachial nuclei and the locus coeruleus of the human brain. 154 21

By means of double immunolabeling procedures it has been possible to demonstrate glucocorticoid receptor (GR) immunoreactivity (IR) in large numbers of various peptidergic neurons of the brain including neurons containing gastrointestinal peptides, opioid peptides, and peptides with a hypothalamic hormone function. For each peptide system, however, marked heterogeneities exist among brain regions. Thus, in the neocortex and the hippocampal formation most of the brain peptide neurons lack GR IR, while the same types of peptide neurons in the arcuate and paraventricular nucleus [e.g. neuropeptide Y (NPY), somatostatin (SRIF) and the cholecystokinin (CCK) neurons] possess strong GR IR. Furthermore, in the arcuate, parvocellular part of the paraventricular nuclei and the central amygdaloid nucleus practically all the peptidergic neurons are strongly GR IR, while in the lateral hypothalamus, mainly the neurotensin (NT) and galanin (GAL) IR neurons are GR IR. These marked differences among areas probably reflect functional differences dependent upon their participation in stress regulated circuits. All the paraventricular NT, corticotropin-releasing factor (CRF), growth hormone-releasing factor (GRF), thyrotropin-releasing hormone (TRH) and SRIF IR neurons appear to contain GR IR, while the luteinizing hormone-releasing hormone (LHRH) IR neurons lack GR IR, underlying the importance of glucocorticoids (GC) in controlling endocrine function. Finally, the GC may influence pain and mood control mainly via effects on enkephalin (ENK) neurons especially in the basal ganglia (mood) and on all beta-endorphin (beta-END) neurons of the arcuate nucleus, while most of the dynorphin neurons are not directly controlled by GC.
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PMID:Central peptidergic neurons as targets for glucocorticoid action. Evidence for the presence of glucocorticoid receptor immunoreactivity in various types of classes of peptidergic neurons. 168 65

The effect of adrenocorticotropin (ACTH) on the release of four regulatory peptides from the anterior pituitary of male rats has been studied using an in vitro perfusion system. Quartered anterior pituitaries from male adult Wistar rats were perfused with buffer containing different concentrations of ACTH and, subsequently, 56 mM KCl. Fractions of 1.5 ml were collected at 3 min intervals and analyzed for vasoactive intestinal peptide (VIP), galanin, 7B2, and substance P, using specific radioimmunoassays. Concentrations of 0.02, 0.1, 0.2, and 0.4 microM ACTH produced increases of 117 +/- 50%, 155 +/- 90%, 163 +/- 14%, and 161 +/- 3% (mean + SE), respectively, of basal release of VIP (P less than 0.001). However, concentrations of 1 microM and 2 microM ACTH suppressed VIP release to 74 +/- 6% and 47 +/- 4%, respectively, compared to basal release (P less than 0.001). Results for galanin release were similar: concentrations of 0.02, 0.1, 0.2, and 0.4 microM ACTH increased galanin release to 129 +/- 4%, 136 +/- 8%, 143 +/- 9%, and 133 +/- 9% of basal release (P less than 0.001) and 1 and 2 microM ACTH provoked a suppression of 52 +/- 7% and 50 +/- 13%, respectively, compared with basal release (P less than 0.001). Doses of ACTH that altered the secretion of VIP and galanin had no effect on 7B2 and substance P release. These results demonstrate that ACTH causes a release of pituitary VIP and galanin in vitro and, moreover, that this is a biphasic phenomenon.
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PMID:Effect of ACTH on VIP and galanin release from the pituitary. 168 92

We investigated immunoreactivity for galanin, a 29-amino acid peptide, in formalin-fixed, paraffin-embedded sections of 123 neuroendocrine tumors. Galanin-immunoreactive cells were found in one of 12 hypothalamic gangliocytomas, nine of 18 adrenal pheochromocytomas, nine of 14 pituitary corticotroph adenomas, and one of two thymic endocrine tumors. In pheochromocytomas, galanin-immunoreactive cells were seen either singly or in clusters. In corticotroph adenomas, many tumor cells were positive for galanin, indicating colocalization of corticotropin and galanin in the same tumor cells. No galanin-immunoreactive cells were noted in four extra-adrenal paragangliomas; 10 medullary carcinomas of the thyroid; 35 endocrine tumors arising in the lung, pancreas, and gastrointestinal tract; and 28 pituitary adenomas composed of cells other than corticotrophs. In nontumorous counterparts of these neuroendocrine tumors, galanin immunoreactivity was observed in nerve cells of the hypothalamus, nerve fibers of the duodenum, and adenohypophyseal cells corresponding to corticotrophs. These findings indicate that galanin expression in neuroendocrine tumors is uncommon and restricted to some tumor types.
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PMID:Galanin immunoreactivity in neuroendocrine tumors. 171 39

Food intake can be increased or decreased after either central or peripheral administration of peptides. Galanin, neuropeptide Y, opioid peptides, growth-hormone-releasing hormone, and desacetyl-melanocyte stimulating hormone increase food intake whereas insulin, glucagon, cholecystokinin, anorectin, corticotropin-releasing hormone, neurotensin, bombesin, cyclo-his-pro, and thyrotropin-releasing hormone reduce food intake. Many of these peptides have reciprocal effects on food intake and sympathetic activity with those peptides that stimulate food intake reducing sympathetic activity and vice versa. In addition, neuropeptide Y specifically increases carbohydrate intake. Galanin and opioid peptides on the other hand increase fat intake whereas enterostatin reduces fat intake. Glucagon decreases protein intake. The effect of peptides on specific nutrients suggests that peptides may work in part by modulating basic feeding mechanisms to lead to the selection of specific nutrients from the diet. This hypothesis might be called a nutrient-specific model of peptide-induced food intake.
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PMID:Peptides affect the intake of specific nutrients and the sympathetic nervous system. 172 38

The knowledge on the neuronal inputs to the locus coeruleus (LC) and their roles in regulating noradrenergic (NA) cellular activity is quite advanced. In recent years, however, about ten neuropeptides were found to be localized in the area of the rodent LC; peptides which may be considered as potential transmitters or modulators acting in this area. Electrophysiological studies performed in vivo and in vitro have revealed that many of these peptides are able to alter LC neuronal activity. Stimulatory effects have been described with vasopressin, substance P, adrenocorticotropin hormone and corticotropin-releasing factor. Depressant effects were seen with galanin, somatostatin, neuropeptide Y and enkephalin. Variable actions were observed in the case of neurotensin. While these findings point to a possible regulatory function of these peptides in this area, precise roles remain unclear. Important information is lacking that would conclusively demonstrate their regulatory functions. It should be determined whether the stimulation of peptidergic cells elicits synaptic effects identical to the ones observed with local exogenous peptide applications. By studying the action of blockers of these transmitter and modulator candidates, we would probably begin to understand their importance in the regulation of tonic and phasic activity components. The LC is generally considered to consist of a homogenous group of neurons. The recent observation that subpopulations of these cells contain peptides as in the case of neuropeptide Y, galanin and vasopressin, points to the possible existence of subgroups of neurons having different functions.
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PMID:Responses of locus coeruleus neurons to neuropeptides. 181 23

The hypothalamus is a major source of afferents to the parabrachial nucleus (PB), but the neurotransmitters in this pathway are largely unknown. In this study, we examine the neuropeptide immunoreactivities of neurons in the hypothalamus that project to the PB by using the combined retrograde fluorescence-immunofluorescence method. After injections of the fluorescent tracer fast blue into the PB, retrogradely labeled neurons were observed in the paraventricular, dorsomedial, ventromedial, median preoptic, and anteroventral periventricular hypothalamic nuclei; in the dorsal, retrochiasmatic, and lateral hypothalamic areas; and in the medial and lateral preoptic areas. Our results show that at least five distinct neuropeptide-immunoreactive cell populations in the hypothalamus project to the PB. In the perifornical lateral hypothalamus, many neurotensin (NT)-, corticotropin-releasing factor-, dynorphin (DYN)-, angiotensin II (AII)-, and galanin-like immunoreactive (-ir) neurons were retrogradely labeled. A cluster of retrogradely labeled neurons in the juxtacapsular lateral hypothalamus stained with an antiserum against alpha-melanocyte stimulating hormone (alpha MSH). Over 50% of the retrogradely labeled cells in the arcuate nucleus were adrenocorticotropin (ACTH)-or alpha MSH-ir. Many alpha MSH- and ACTH-ir, and a few DYN-, NT- and AII-ir neurons in the retrochiasmatic area were retrogradely labeled. Only small numbers of double-labeled neurons were found in the paraventricular nucleus, and, of these, enkephalin-ir and dynorphin-ir neurons were the most common. Somatostatin-ir cells in the hypothalamus were rarely double-labeled. The chemical coding of these hypothalamic projections to the PB may provide important clues to the functional organization of these descending pathways.
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PMID:Neuropeptide organization of the hypothalamic projection to the parabrachial nucleus in the rat. 197 10

Hypothalamic neuropeptides play a role in appetite and weight regulation. Food restriction for 2 weeks and food deprivation for 4 days were used as models to characterize the effects of weight loss on hypothalamic peptide gene expression in male and female rats. We used in situ hybridization to examine the mRNA levels of hypothalamic peptides which stimulate and inhibit food intake and found selective effects primarily in the arcuate nucleus. Neuropeptide Y (NPY) mRNA was increased and pro-opiomelanocortin (POMC) and galanin (GAL) mRNA were decreased in the hypothalamic arcuate nucleus and corticotropin-releasing hormone (CRH) mRNA was decreased in the hypothalamic paraventricular nucleus in male and female food-restricted and food-deprived rats. Food restriction produced larger changes in peptide mRNA expression than did food deprivation. Changes in NPY, POMC and CRH gene expression induced by food restriction were greater in male than female rats. Elevated NPY and reduced CRH gene expression may be a compensatory physiological response to restore food intake in food-restricted and food-deprived animals. The discrete changes in NPY, POMC, GAL and CRH gene expression in food-restricted and food-deprived animals suggest the involvement of these peptides in abnormal appetitive behavior and weight loss associated with human eating disorders.
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PMID:Altered expression of hypothalamic neuropeptide mRNAs in food-restricted and food-deprived rats. 217 53


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