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)

The medial preoptic nucleus (MPN) is a sexually dimorphic complex with three major subdivisions. The cell-dense central (MPNc) and medial (MPNm) subdivisions are larger in male rats, while the cell-sparse lateral subdivision (MPNl) occupies a majority of the nucleus in females. In the present study we evaluated the distribution of possible monoaminergic and peptidergic cells and fibers within the MPN, as well as in adjacent regions of the medial preoptic area of the adult male rat. For this, we used an indirect immunohistochemical method with antisera to serotonin (5HT), dopamine beta-hydroxylase (DBH), tyrosine hydroxylase (TH), neuropeptide Y (NPY), cholecystokinin (CCK), vasoactive intestinal polypeptide (VIP), substance P (SP), neurotensin (NT), corticotropin-releasing factor (CRF), luteotropin-releasing hormone (LRH), somatostatin (SS), thyrotropin-releasing hormone (TRH), oxytocin (OXY), vasopressin (VAS), adrenocorticotropic hormone (1-24; ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), leucine-enkephalin (L-ENK), and calcitonin gene-related peptide (CGRP). The results suggest that cell bodies and/or fibers crossreacting with all of these putative neurotransmitters are differentially distributed within the MPN. Within the MPNm, the densest plexuses of fibers were stained with antisera to SP and NPY, while moderate densities of fibers were stained with anti-DBH, SS, CCK, CGRP, ACTH, and alpha-MSH, and only a few fibers were stained with anti-5HT, TH, NT, VAS, and L-ENK. Moderate numbers of SP- and L-ENK-immunoreactive cell bodies, and a few SS-, NT-, CRF-, and TRH-stained cell bodies were also found within the MPNm. The MPNc contained a dense plexus of CCK-immunoreactive fibers, as well as a few CRF-immunoreactive fibers. Both fiber types were localized almost exclusively to this subdivision, while most of the others studied here appeared to avoid it selectively. This suggests that there are relatively few inputs to the MPNc, and that they tend to avoid other parts of the nucleus, although moderate densities of DBH- and NPY-immunoreactive fibers were found in both the MPNm and MPNc. The MPNc contained several CCK-immunoreactive cell bodies as well as a moderate number of TRH-stained cell bodies. Both cell types were nearly completely localized to the MPNc. The major inputs to the MPNl studied here appear to be stained with antisera to 5HT and L-ENK, although moderate numbers of NT- and CRF- immunoreactive fibers were also found in this part of the nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Neurotransmitter specificity of cells and fibers in the medial preoptic nucleus: an immunohistochemical study in the rat. 242 28

The purpose of the present study was to quantify the extent to which several peptides and serotonin coexist with substance P or somatostatin in selected lumbar dorsal root ganglia of the cat. The technique for the simultaneous visualization of two antigens by immunofluorescence was used to investigate the coexistence of neuropeptides in the lumbar dorsal root ganglia of colchicine-treated cats. Perikarya immunoreactive for calcitonin gene-related peptide, galanin, leu-enkephalin, somatostatin, and substance P were visualized in both the lumbar 5 and 6 dorsal root ganglia. In contrast, no immunoreactivity was observed for adipokinetic hormone, bombesin, dynorphin A, met-enkephalin, oxytocin, tyrosine hydroxylase, thyrotropin-releasing hormone, vasopressin, vasoactive intestinal peptide, or serotonin in either ganglion examined. Substance P coexisted with calcitonin-gene-related peptide, somatostatin, and leu-enkephalin. Somatostatin was colocalized with calcitonin gene-related peptide, leu-enkephalin, and substance P but coexisted with galanin minimally. The cell area of immunoreactive perikarya was also examined. Data concerning the cross-sectional area of immunoreactive cells indicated that somatostatin-immunoreactive perikarya were generally the largest population observed (up to approximately 6,000 microns2). Somatostatin and calcitonin gene-related peptide, as well as substance P and calcitonin gene-related peptide, coexisted in populations of cell bodies that had a smaller size (less than 2,000 microns2). These results suggest that certain peptides which coexist in the dorsal root ganglia may provide histochemical markers for functional groups of primary afferent neurons.
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PMID:Lumbar dorsal root ganglia of the cat: a quantitative study of peptide immunoreactivity and cell size. 247 1

In this study we have investigated the presence of nerve fibers containing dopamine, thyrotropin-releasing hormone (TRH) and neuropeptide Y (NPY) in the pars intermedia of the crested newt and we have examined the possible effect of these neurohormones on the release of alpha-melanotropin (alpha-MSH) by neurointermediate lobes in vitro. By means of immunohistochemistry, we observed the presence of tyrosine hydroxylase (TH)-immunoreactive fibers in the pars intermedia of the crested newt. Using a specific antiserum to dopamine, these fibers appeared to be mainly dopaminergic in nature. Unlike anurans, urodele amphibians do not exhibit TRH or NPY-like immunoreactivity in the pars intermedia. A perifusion system technique for newt pituitaries was developed to investigate the effect of dopamine, TRH and NPY on alpha-MSH secretion. Administration of increasing concentrations of dopamine (from 10(-9) to 10(-5)M) induced a dose-related inhibition of alpha-MSH release. This inhibitory effect was mimicked by the dopamine agonist apomorphine (10(-6)M). In contrast, the secretory activity of the newt pars intermedia was not affected by administration of synthetic TRH or NPY (up to 10(-7) and 10(-6)M, respectively). These results indicate that the neurotransmitter dopamine likely plays a pivotal role in the regulation of melanotropin secretion in urodele amphibians.
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PMID:Innervation of the pars intermedia and control of alpha-melanotropin secretion in the newt. 251 95

Opioids and some alpha 2-adrenergic agonists are both known for their potent hypotensive actions following local application to the rostral ventrolateral medulla (RVL), in particular the region containing the C1 adrenergic neurons. We sought to determine whether coexistence and/or synaptic interactions might account for the commonality of cardiovascular responses to opioids and catecholamines in the RVL. Dual light and electron microscopic (EM) immunoperoxidase labeling of a rat monoclonal antibody against the opioid peptide Leucine5 (Leu5)-enkephalin and immunoautoradiographic localization of a rabbit antiserum against the catecholamine synthesizing enzyme tyrosine hydroxylase (TH) were examined in single sections through the RVL of adult colchicine-pretreated rats. Cross-reactivity of the enkephalin antibody was most intense with Leu5-enkephalin. Methionine5-enkephalin as well as dynorphin A, but not beta-endorphin, were also recognized by the antisera. By light microscopy, the Leu5-enkephalin-like immunoreactivity (LE-LI) was identified by peroxidase reaction product in perikarya and processes. Most of the perikarya containing LE-LI were located dorsolaterally or ventromedially to those showing immunoautoradiographic labeling for TH. However, a few perikarya appeared to contain both LE-LI and TH-immunoreactivity (TH-I) which were difficult to differentiate by light microscopy. By EM, perikarya and dendrites immunoreactive for LE, TH, and both LE and TH were readily distinguishable. Perikarya and dendrites immunoautoradiographically labeled for TH alone were more numerous than those containing LE-LI or TH-I and LE-LI. Axon terminals also were immunolabeled either for one or both reaction products. However, the TH-labeled neurons constituted one of the primary (42% from a total of 118) targets of terminals containing LE-LI. Additionally, some of these terminals containing LE-LI shared a common target with TH-labeled terminals. These common target neurons contained either TH-I or TH-I and LE-LI. In most cases, the identified junctions were symmetric and the terminals with LE-LI (0.4-1.2 microns in diameter) contained either (1) a few small clear vesicles (scv's) and numerous intensely immunoreactive large (100-150 nm) dense-core vesicles (dcv's); or (2) many scv's and from 0-6 dcv's of a somewhat smaller (80-120 nm) diameter. The latter type of terminal was more consistently dually labeled for TH. The remaining terminals containing LE-LI formed synaptic junctions with unlabeled perikarya or dendrites (32%), were in apposition to other unlabeled as well as TH or LE- and TH-containing terminals (4%) or were without recognizable specializations within the plane of section (22%).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Ultrastructural basis for interactions between central opioids and catecholamines. I. Rostral ventrolateral medulla. 256 65

The three major classes of neurons in the paraventricular nucleus (PVH) provide a rich model for studying hormonal and neural influences on multiple neuropeptides expressed in individual cells. A great deal of previous work has examined this problem at the immunohistochemical level, where hormonal and neural influences on peptide levels have been established. In situ hybridization methods were used here to determine whether these effects are accompanied by measurable changes in neuropeptide mRNA levels. In the first series of experiments, the time-course of corticosterone replacement effects on corticotropin-releasing hormone (CRH) mRNA levels in parvicellular neuroendocrine cells of adrenalectomized animals were determined, and a dose-response curve was established. CRH mRNA hybridization remains maximal with plasma levels of steroid up to about 50 ng/ml, then declines sharply between about 60-130 ng/ml, and is just detectable at higher levels. We confirmed that corticosterone decreases vasopressin mRNA levels in this cell group and showed that levels of preproenkephalin mRNA are also decreased, whereas no significant changes in cholecystokinin, beta-preprotachykinin, and angiotensinogen mRNA levels could be detected. Thus, corticosterone decreases some neuropeptide mRNA levels and has no influence on others in this cell group. Tyrosine hydroxylase mRNA hybridization is also unaffected in this part of the nucleus. In a second group of experiments, the cell-type specificity of corticosterone influences was examined. It was found that while the hormone depresses CRH mRNA levels in parvicellular neurons, it increases such levels in PVH neurons with descending projections, in certain magnocellular neurosecretory neurons, and in a part of the central nucleus of the amygdala, whereas no influence was detected in the rostral lateral hypothalamic area. Furthermore, the stimulatory effects of corticosterone have different threshold levels in different cell groups. Thus, in different types of neurons, corticosterone may increase, decrease, or have no influence on CRH mRNA levels. In contrast, while corticosterone depresses vasopressin mRNA levels in parvicellular CRH neurons, it has no obvious effects on vasopressin mRNA levels in magnocellular or descending neurons; as with CRH, the effects of corticosterone on vasopressin mRNA levels are cell-type specific. In a third series of experiments it was shown that glucocorticoid receptor and mineralocorticoid receptor mRNAs are found in all three cell types in the PVH and that corticosterone tends to produce modest increases in mRNA levels for both receptors. Finally, it was shown that unilateral catecholamine-depleting knife cuts do not change mRNA levels for any of the neuropeptides (or steroid hormone receptors) examined here, although dramatic changes in neuropeptide levels themselves have been shown.4+
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PMID:Differential steroid hormone and neural influences on peptide mRNA levels in CRH cells of the paraventricular nucleus: a hybridization histochemical study in the rat. 256 87

Indirect immunofluorescence histochemistry and receptor autoradiography were used to study the localization of transmitter-/peptide-containing neurons and peptide binding sites in the mediobasal hypothalamus in normal rats and in rats treated neonatally with repeated doses of the neurotoxin monosodium-glutamate (MSG). In the arcuate nucleus, the results showed a virtually complete loss of cell bodies containing immunoreactivity for growth hormone-releasing factor (GRF), galanin (GAL), dynorphin (DYN), enkephalin (ENK), corticotropin-like intermediate peptide (CLIP), neuropeptide Y (NPY), and neuropeptide K (NPK). Tyrosine hydroxylase(TH)-glutamic acid decarboxylase(GAD)-, neurotensin(NT)- and somatostatin(SOM)-immunoreactive (IR) cells were, however, always detected in the ventrally dislocated, dorsomedial division of the arcuate nucleus. In the median eminence, marked decreases in numbers of GAD-, NT-, GAL-, GRF-, DYN-, and ENK-IR fibers were observed. The numbers of TH-, SOM- and NPY-IR fibers were in contrast not or only affected to a very small extent, as revealed with the immunofluorescence technique. Biochemical analysis showed a tendency for MSG to reduce dopamine levels in the median eminence of female rats, whereas no effect was observed in male rats. Autoradiographic studies showed high to moderate NT binding sites, including strong binding over presumably dorsomedial dopamine cells. In MSG-treated rats, there was a marked reduction in GAL binding in the ventromedial nucleus. The findings implicate that most neurons in the ventrolateral and ventromedial arcuate nucleus are sensitive to the toxic effects of MSG, whereas a subpopulation of cells in the dorsomedial division of the arcuate nucleus, including dopamine neurons, are not susceptible to MSG-neurotoxicity. The results indicate, moreover that the very dense TH-IR fiber network in the median eminence predominantly arises from the dorsomedial TH-IR arcuate cells, whereas the GAD-, NT-, GAL-, GRF- and DYN-IR fibers in the median eminence to a large extent arise from the ventrolateral arcuate nucleus. Some ENK- and NPK-positive cells in the arcuate nucleus seem to project to the lateral palisade zone of the median eminence, but most of the ENK-IR fibers in the median eminence, located in the medial palisade zone, seem to primarily originate from an area(s) located outside the arcuate nucleus, presumably the paraventricular nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Neurotransmitters, neuropeptides and binding sites in the rat mediobasal hypothalamus: effects of monosodium glutamate (MSG) lesions. 256 86

Male rats were exposed to severe 14 day immobilization stress. Body weight, body temperature, food and water intake, behavioral parameters, and serum corticosterone levels were measured during and after the stress period. On the 7th day after cessation of stress the experimental animals together with the control rats were taken to immunocytochemical analysis involving morphometry and microdensitometry of tyrosine hydroxylase (TH), 5-hydroxytryptamine (5-HT), various neuropeptide, and glucocorticoid receptor (GR) immunoreactivities (IRs) in a large number of regions of the central nervous system. In addition, adrenocorticotropic hormone (ACTH) IR was analyzed in the pituitary gland. Seven days following cessation of the chronic stress food intake, total locomotion and forward locomotion had been restored to normal. Serum corticosterone levels appeared to remain increased even 6 days following cessation of the chronic immobilization stress, probably caused by increased release of ACTH. Paraventricular corticotropin releasing hormone (CRF) IR was negatively correlated with the pituitary ACTH IR, indicating that the increase in ACTH release was produced by an increased release of CRF from the hypothalamus. The major immunocytochemical change observed 7 days after cessation of stress was a disappearance of 5-HT IR in the 5-HT cell groups B1, B2, B3, and B7. 5-HT IR in nerve terminals was only affected in the dorsal horn, where 5-HT IR was increased in the substantia gelatinosa. GR IR was found to be significantly increased in monoaminergic cell groups: serotoninergic B7, dopaminergic A12, and noradrenergic A1, A2, and A6. A trend for a reduction of TH IR was observed in nigral DA cells associated with significant reductions in TH IR in striatal DA nerve terminals. Finally, increases in 5-HT and substance P (SP) IR were found in the nerve terminals of the substantia gelatinosa of the cervical spinal cord in the stress group. In the present experimental model evidence has been obtained for a maintained activation of the hypothalamic-pituitary-adrenal axis as evaluated 7 days after cessation of severe chronic immobilization stress. The reduction of 5-HT IR in various 5-HT cell groups indicates a reduction of 5-HT synthesis, which may also be associated with reduced 5-HT release from the nerve terminals, since no depletion was observed in terminal regions and in one case an increase in 5-HT IR was noted (substantia gelatinosa).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Chronic immobilization stress: evidence for decreases of 5-hydroxy-tryptamine immunoreactivity and for increases of glucocorticoid receptor immunoreactivity in various brain regions of the male rat. 276 Jun 6

No immunoreactive axons were detected with an antiserum against tyrosine hydroxylase in the rabbit intermediate lobe (IL), which thus appears to be devoid of dopaminergic (DA) innervation. Dopamine and its agonists, which classically inhibit alpha-MSH release have no inhibitory effects on rabbit IL superfused in vitro but, paradoxically, stimulate alpha-MSH release. D2 type DA receptors, known to mediate inhibitory control of dopamine on melanotropic cells, and detectable by their affinity for (3H)-spiroperidol, were as previously reported absent from the rabbit IL. The absence of (3H)-spiroperidol binding sites in the IL was further confirmed on rabbit pituitary sections by radioautography. The mechanism of DA stimulation is still not clear, but might be tentatively explained by interference with other receptors involved in the stimulation of the gland. The lack of DA inhibitory control over the rabbit IL is an exception among the species so far studied.
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PMID:Absence of inhibitory dopaminergic control of the rabbit pituitary gland intermediate lobe. 286 83

We surveyed retinas of Raja erinacea, Mustelus canis, and Squalus acanthias for neurotransmitter substances by using antisera directed against the substances themselves or against their synthesizing enzymes. Both the peroxidase-antiperoxidase (PAP) and indirect fluorescent techniques were employed to visualize the primary antisera. In all three species positive results were obtained with antisera directed against tyrosine hydroxylase (TOH), glutamic acid decarboxylase (GAD), serotonin (5-HT), and leucine enkephalin (Lenk). Antisera directed against glucagon, neurotensin, beta-endorphin, vasoactive intestinal peptide, or bombesin failed to show any specific staining. Immunoreactivity was located in amacrine, interplexiform, and horizontal cells as well as in axons of the optic fiber layer. The four antisera labelled different amacrine cell classes, distinguished on the bases of perikaryal morphology and the distribution of cell processes in the inner plexiform layer (IPL). Amacrine cells that labelled with the same marker were seen to have different morphologies in the species studied. Thus, TOH-like immunoreactivity was distributed in layers 1, 3, and 5 of the IPL in Mustelus but only in layers 1 and 3 in Raja retina. GAD-like immunoreactivity was found diffusely over all layers of the IPL in Raja, but in Mustelus it was confined primarily to layers 1, 3, and 5 of the IPL. Lenk- and 5-HT-like immunoreactivities showed similar species variations. Two neurochemical classes of interplexiform cell were identified in this study. In Mustelus GAD-like and Lenk-like immunoreactive interplexiform cells were seen whereas in Raja only GAD-positive interplexiform cells were detected. In squalus no unequivocal demonstration of any interplexiform cell was made with these antisera. The GAD antiserum also labelled a subset of the horizontal cells in the dorsal retina of Raja. TOH and 5-HT-antisera labelled axons in the optic fiber layer of all three species but reactive ganglion cell perikarya were not identified.
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PMID:Retinal neurochemistry of three elasmobranch species: an immunohistochemical approach. 286 65

Recent studies suggest that neurons containing adrenocorticotropin and catecholamines are localized to similar areas of the brain. In this immunocytochemical study, the distributions of neurons and terminals containing adrenocorticotropin and tyrosine hydroxylase, the first enzyme in the catecholamine biosynthetic pathway, were compared using the peroxidase-antiperoxidase technique. Neurons containing adrenocorticotropin and tyrosine hydroxylase formed overlapping hyperbolic lamina in the mediobasal hypothalamus. Although adrenocorticotropin and tyrosine hydroxylase containing neurons often formed small clusters, no double labeled cells were observed. Overlap also occurred between adrenocorticotropin and tyrosine hydroxylase terminal fields in several diencephalic nuclei including the periventricular hypothalamic gray and paraventricular thalamus. In contrast, other regions displayed striking compartmentalization of terminal fields; for example, in both the paraventricular hypothalamus and central nucleus of the amygdala, adrenocorticotropin was located in ventral and tyrosine hydroxylase in more dorsal aspects of the nuclei. Adjacent sections also showed a close correspondence between adrenocorticotropin terminals and tyrosine hydroxylase cell bodies in paraventricular, periventricular, dorsomedial and ventral hypothalamic nuclei. These data provide anatomical substrates for potential functional interactions between catecholamine and adrenocorticotropin systems in forebrain.
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PMID:Anatomical evidence for interactions between catecholamine- and adrenocorticotropin-containing neurons. 287 20


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