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)

We have investigated the presence of ACTH, alpha-MSH and beta-endorphin, three peptides which derive from the multifunctional precursor protein proopiomelanocortin (POMC) in the brain of the rainbow trout Salmo gairdneri. Using both the indirect immunofluorescence and peroxidase-antiperoxidase techniques, a discrete group of positive cells was identified in the hypothalamus, within the anterior part of the nucleus lateralis tuberis. alpha-MSH-containing neurons represented the most abundant immunoreactive subpopulation. Coexistence of alpha-MSH, ACTH and beta-endorphin was observed in the lateral part of the nucleus. ACTH- and beta-endorphin-containing cells were mainly distributed in the rostral and caudal regions of the nucleus. In the medial portion of the nucleus lateralis tuberis, numerous cells were only stained for alpha-MSH. Moderate to dense plexuses of immunoreactive fibers were observed in the ventral thalamus and the floor of the hypothalamus. Some of these fibers projected towards the pituitary. The concentrations of ACTH, alpha-MSH and beta-endorphin-like immunoreactivities were measured in microdissected brain regions by means of specific radioimmunoassays. Diencephalon, mesencephalon and medulla oblongata extracts gave dilution curves which were parallel to standard curves. The highest concentrations of POMC-derived peptides were found in the diencephalon (alpha-MSH: 4.28 +/- 0.43 ng/mg prot.; ACTH: 1.08 +/- 0.09 ng/mg prot.; beta-endorphin: 1.02 +/- 0.1 ng/mg prot.), while lower concentrations were detected in the mesencephalon, medulla oblongata and telencephalon. The present results demonstrate that various peptides derived from POMC coexist within the same cell bodies of the fish hypothalamus. Taken together, these data suggest that expression and processing of POMC in the fish brain is similar to that occurring in pituitary melanotrophs.
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PMID:Proopiomelanocortin (POMC)-related peptides in the brain of the rainbow trout, Salmo gairdneri. 256 Jan 77

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

A preembedding immunogold staining (IGS) procedure was developed to identify beta-endorphin/adrenocorticotropic hormone immunoreactive neurons at the light and electron microscopic levels. Colchicine-treated rats were perfused with Nakane's periodate-lysine-paraformaldehyde fixative. Vibratome sections were incubated in primary antisera followed by goat anti-rabbit immunoglobulin G coupled to 16 nm colloidal gold, and, in some cases, rabbit immunoglobulin G coupled to gold. The appearance to pink to light red perikarya, corresponding to colloidal gold deposition at antigenic sites, was monitored under the light microscope. Positive cell bodies in the arcuate region sometimes extended lateral to the nucleus. Only proximal portions of neuronal processes were stained. At the ultrastructural level, colloidal gold labeled the periphery of 90-110 nm dense neurosecretory granules in the perikaryal cytoplasm and a few proximal axons. Clusters of gold particles, appearing free in the neuroplasm, actually labeled secretory granules in adjacent thin sections. Granules associated with the Golgi apparatus were not stained. Colloidal gold labeling of mature beta-endorphin granules, but not progranules, in rat hypothalamic neurons was confirmed using the peroxidase-antiperoxidase technique. The results correlate well with data on the intracellular processing of pro-opiomelanocortin in pituitary cells and prepropressophysin in the paraventricular nucleus. These data demonstrate the first application of the preembedding colloidal gold staining method for the identification of intracellular antigens within the central nervous system. The IGS method provides a definitive marker for single or double labeling of nervous tissue at both the light and electron microscopic levels.
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PMID:Preembedding colloidal gold immunostaining of hypothalamic neurons: light and electron microscopic localization of beta-endorphin-immunoreactive perikarya. 258 27

Cells whose nuclei accumulated 3H-estradiol were identified autoradiographically in fixed, frozen sections of colchicine-treated rat hypothalamus (n = 3 animals). After autoradiogram development, these sections were subjected to immunocytochemistry using rabbit antirat prolactin antiserum and the avidin-biotinylated horseradish peroxidase method. In the hypothalamus, a substantial subset of the neurons containing immunoreactive prolactin accumulated 3H-estradiol in their nuclei: of 3, 642 immunoreactive cells examined, 1,216 had autoradiographically labeled nuclei, or about 33%. The immunoreactive prolactin neurons with autoradiographically labeled nuclei were located in the medial basal hypothalamus intermingled with immunoreactive prolactin neurons whose nuclei were not labeled autoradiographically. Since hypothalamic immunoreactive prolactin neurons have a rich and widely distributed fiber system, the present results suggest that estrogen, acting through a subset of these neurons, can modify directly the neuronal activity of several brain regions which regulate diverse aspects of the reproductive effort. Also, since immunoreactive prolactin and immunoreactive beta-endorphin exist in the same hypothalamic cell population, opioid peptides derived from pro-opiomelanocortin may mediate some effects of estrogen on the neural circuitry regulating reproduction.
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PMID:A subset of neurons containing immunoreactive prolactin is a target for estrogen regulation of gene expression in rat hypothalamus. 271 46

Forty-one-residue corticotropin-releasing factor is a physiologically significant mediator of the hypothalamic control of corticotropin secretion by the anterior pituitary gland. This releasing hormone is produced by parvicellular neurons in the hypothalamic paraventricular nucleus that project to the external zone of the median eminence. Recent immunocytochemical evidence based on work with a rabbit antiserum against rat corticotropin-releasing factor (code rC70) suggests that about half of the parvicellular corticotropin-releasing factor-containing neurons in the hypothalamic paraventricular nucleus synthesize vasopressin, another potent corticotropin secretagogue, while the rest of the cells do not. If this is indeed the case, the neurohumoral control of corticotropin release may be mediated via distinct hypothalamic effector pathways utilizing releasing hormone cocktails of varying composition. In the present study we have examined the specificity of various antisera against rat corticotropin-releasing factor in immunocytochemical staining. Male Wistar rats pretreated with colchicine were used throughout. The brain was fixed by perfusion with a Zamboni type fixative solution. Vibratome sections of the hypothalamus were immunostained with three different primary antisera (codes rC70, rCRF-3, oCRF-N) using the peroxidase-antiperoxidase or avidin-biotin complex methods. All three antisera stained cell groups previously described to be immunopositive for corticotropin-releasing factor. Most notably, however, rC70 labelled a significant number of additional cells, most readily identified in the arcuate and suprachiasmatic nuclei, as well as in the dorsolateral hypothalamic area caudal to the paraventricular nucleus.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunocytochemical detection of corticotropin-releasing factor: multiple cross-reactions of a widely used carboxy-terminally directed corticotropin-releasing factor antiserum (code rC70) in rat hypothalamus. 278 48

An immunocytochemical study was performed by the indirect peroxidase method on the pituitary tumour of 37 patients with clinical and biological signs of silent adenoma. Antisera were used against human PRL, human GH, ACTH1-24, human ACTH17-39, alpha-melanocyte stimulating hormone (alpha-MSH), human beta-endorphin, alpha-subunit of hCG (hCG-alpha), and beta-subunits of human LH (LH-beta), human FSH (FSH-beta) and human TSH (TSH-beta). Immunostaining in at least 5% of the tumour cell population, with one or more antisera, was present in 13 cases; hCG-alpha immunostaining was the one most frequently observed. Combined immunostaining was found in 7 cases. Exclusive immunostaining was present in 6 cases: 4 with hCG-alpha, 1 with ACTH1-24 and 1 with TSH-beta. It is concluded that a significant number of silent pituitary adenomas show a certain secretory pattern of pituitary hormones or subunits of glycoprotein hormones as revealed by the immunocytochemistry.
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PMID:The immunocytochemical heterogeneity of silent pituitary adenomas. 284 Jul 93

Lectin binding sites of adrenocorticotropic hormone (ACTH) secretory granules of human pituitary adenomas and of nonadenomatous pituitary tissue adjacent to adenomas were studied by postembedding immunocytochemical doublestaining on ultrathin sections followed by electron microscopy. The specific hormones produced by the secretory granules were identified by labeling one side of the section with anti-human pituitary hormone antibodies conjugated to gold particles. Simultaneously, the other side was labeled with horseradish peroxidase-lectin to reveal lectin binding sites. Specimens were obtained from four human ACTH-producing pituitary adenomas and from nonadenomatous pituitary tissue surrounding three other adenomas. The four ACTH-producing adenomas showed either weak or negative reactions with concanavalin A, whereas the nonadenomatous ACTH-producing pituitary cells reacted strongly with concanavalin A. Moreover, ACTH secretory granules were significantly larger in the nonadenomatous cells than in adenoma cells. Differences in biochemical structure and ultrastructure between nonadenomatous (normal) pituitary cells and adenoma cells secreting the same specific hormones were demonstrated, and the clinical implications of the results were discussed.
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PMID:Differences in glycoconjugates of adrenocorticotropic hormone-secretory granules between nonadenomatous pituitary cells and adenoma cells as detected by double labeling. 284 95

The distribution of immunoreactive alpha-melanocyte-stimulating hormone (alpha-MSH) in the central nervous system and pituitary of the elasmobranch fish Scyliorhinus canicula was determined by the indirect immunofluorescence and the peroxidase-antiperoxidase methods using a highly specific antiserum. Perikarya containing alpha-MSH-like immunoreactivity were localized in the dorsal portion of the posterior hypothalamus, mainly in the tuberculus posterioris and sacci vasculosus nuclei. Immunoreactive alpha-MSH cell bodies were found in the dorsal wall and ventral region of the caudal part of the tuberculum posterioris. These structures were densely innervated by fine beaded immunoreactive fibers. Some alpha-MSH immunoreactive cells were occasionally detected in the ventral part of the nucleus periventricularis. Scattered cell bodies and fibers were also observed in the dorsal wall of the posterior recess. Outside the hypothalamus very few fibers were detected in the dorsal thalamus and mesencephalon. No immunoreactivity was found in any other parts of the brain. The alpha-MSH immunoreactive material localized in the brain was characterized by combining high-performance liquid chromatography (HPLC) analysis and radioimmunological detection. Brain and pituitary extracts exhibited displacement curves which were parallel to that obtained with synthetic alpha-MSH. The concentrations of alpha-MSH immunoreactive material were determined in 5 different regions of the brain. The highest concentration was found in the hypothalamus. HPLC analysis resolved two major forms of immunoreactive alpha-MSH in the hypothalamus, which had been same retention times as des-N alpha-acetyl-alpha-MSH and its sulfoxide derivative. These results provide the first evidence for the presence of alpha-MSH-like peptides in the fish brain.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Alpha-melanocyte-stimulating hormone (alpha-MSH) in the brain of the cartilagenous fish. Immunohistochemical localization and biochemical characterization. 285 62

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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