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 effects of various neurogenic peptides and neurotransmitter substances on the release of ACTH induced by hypothalamic corticotropin releasing factor (HY-CRF) were investigated using monolayer cultured anterior pituitary cells. Test substances were given in combination with 0.05-0.1 hypothalamic extract (HE)/ml, because HE evoked a significant ACTH release and a linear dose response relationship was demonstrated sequentially between 0.0165 HE/ml and 0.5 HE/ml. Relative high doses of lysine-vasopressin showed a slight additive effect on the release of ACTH induced by 0.1 HE/ml. Leu-enkephalin, dopamine, prostaglandin E1 and E2 slightly reduced the release of ACTH induced by HY-CRF, but the inhibitory effect of these substances were not dose-related. Other tested substances including luteinizing hormone releasing hormone, thyrotropin releasing hormone, somatostatin, melanocyte stimulating hormone release inhibiting factor, beta-endorphin, neurotensin, substance P, vasoactive intestinal polypeptide, angiotensin II, norepinephrine, serotonin, acetylcholine, histamine and gamma-amino butyric acid showed neither agonistic nor antagonistic effect on the release of ACTH induced by HY-CRF. These results indicate that the release of ACTH is controlled specifically by HY-CRF and corticosterone, and modified slightly by some other substances such as vasopressin and prostaglandins, and that the effect of most other neurogenic peptides and neurotransmitter substances is negligible or non-physiological at the pituitary level.
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PMID:ACTH release in pituitary cell cultures. Effect of neurogenic peptides and neurotransmitter substances on ACTH release induced by hypothalamic corticotropin releasing factor (CRF). 3 43

Denaturing solvents have been used to determine the molecular weight of the adrenocorticotropic hormone (ACTH) activity in mouse pituitary, in an ACTH secreting mouse pituitary tumor cell line (AtT-20/D-16v), and in the tissue culture medium from the pituitary tumor cells. ACTH activity was quantitated by radioimmunoassay and by bioassay. It is possible to utilize guanidine hydrochloride or sodium dodecyl sulfate in characterizing the multiple forms of ACTH because treatment of porcine ACTH (the 39 amino acid polypeptide form of ACTH, alpha(1-39)), pituitary extracts, tumor cell extracts, and tumor cell tissue culture medium with these denaturants does not diminish the immunological ACTH activity. Based on gel filtration in the presence of guanidine hydrocholoride, extracts of the pituitary tumor cells and the mouse pituitary contain three distinct molecular weight classes of ACTH activity. The major form of ACTH has a molecular weight similar to alpha(1-39) (molecular weight 4000-5500), but there are significant amounts of two higher molecular weight forms of ACTH: molecular weight 6500-9000 and molecular weight 20,000-30,000. The 6500-9000 molecular weight form of ACTH is the major form of ACTH in the tissue culture medium; there is no peak of alpha(1-39) size ACTH in the medium. In the radioimmunoasay all three forms of ACTH generate competitive binding curves parallel to that of porcine alpha(1-39); in the bioassay (stimulation of steroidogenesis in a mouse adrenal tumor cell line) the dose response curve for each of the molecular forms of ACTH is parallel to that for porcine alpha(1-39).
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PMID:High molecular weight forms of adrenocorticotropic hormone in the mouse pituitary and in a mouse pituitary tumor cell line. 16 85

The affinity for antiserum to the multipotent lipotropic hormone (beta-LPH) was tested by immunohistochemical staining of all known cell types in normal and certain abnormal mouse, rat, and human pituitaries. Results indicate that beta-LPH has ACTH, MSH, LH and StH(GH) immunologically cross-reacting determinants. Affinities of anti-LPH for TtH and MtH (prolactin) were not detected in normal pituitaries, but thyrotropic tumor cells reacted with anti-LPH. Absorption experiments confirm that the single polypeptide hormone of the pituitary, beta-LPH, is coded for ACTH and MSH activities. The multi-functional hormone, LPH probably is secreted by the adrenotropes. In addition to ACTH and MSH, it probably contains other antigenic and biologic determinants. Some of these may accentuate its lipotropic activities; others may be incidental. These are points calling for further correlated structural, biologic, and immunologic investigations.
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PMID:Multipotent lipotropic hormones. In search of a pituitary cell producing multipotent LPH. 17 14

The localization of various neuropeptides is described in the gut and in the hypothalamus in the rat. Evidence is given for the presence of material resembling corticotropin-like intermediate peptide in arcuate and periarcuate neurons, projecting to various hypothalamic nuclei, limbic areas and the thalamus. beta-Endorphin and glucagon decrease dopamine turnover in the median eminence, while secretin increases dopamine turnover and vasoactive intestinal polypeptide (VIP) has no effect. beta-Endorphin, VIP, secretin, and glucagon all produce discrete changes in norepinephrine turnover in various hypothalamic nuclei. Mainly increases of norepinephrine turnover were observed. These catecholamine turnover changes appear to cause changes in the secretion of prolactin and growth hormone. The results therefore indicate that gut hormones and opioid peptides may act directly on the hypothalamus on specific types of receptors to participate in the control of hypothalamic functions such as control of hormone secretion from the anterior pituitary and of food intake. It seems possible that gastrointestinal peptides released from the gastrointestinal tract into the circulation under certain circumstances could reach the hypothalamus and modulate its activity via the above-mentioned mechanisms. It may therefore be speculated that disturbances in gastrointestinal functions could lead to pathological changes in food intake via modulation of hypothalamic activity.
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PMID:Localization and possible function of peptidergic neurons and their interactions with central catecholamine neurons, and the central actions of gut hormones. 22 24

Endorphins are peptides with opiate-like action synthesized in various tissue, e.g. in intestine and central nervous system. Exact characterization of opioid-specific receptors and sensitive biological test assays for opioids were prerequisites for the discovery of these substances. Met- and leu-enkephalin were the first endorphins discovered. Both are pentapeptides. One of them, namely met-enkephalin (H-Tyr-Gly-Gyl-Phe-Met-OH) is likely to be a fragment of the peptides alpha- and beta-endorphin, both showing opioid-like actions, as well as of beta-lipotropin, a polypeptide showing no opioid-like activity: all these peptides include the pentapeptide met-enkephalin within their molecules. beta-liportropin and ACTH are likely to be fragments of a common precursor. At least both enkephalins (which are studied better as yet than the other endorphins) are supposed to be formed in the soma of the neuron and transported to the nerve ending, where they are released. They seem to have the function of neuromodulator or even of neurotransmitters. The pharmacological actions of endorphins resemble those of "classical opiates", both having e.g. analgesic effects. Both enkephalins are, among various other brain and spinal cord areas, localized in those areas which seem to be of particular relevance for perception and transmission of pain. They might, under certain conditions, play some part in the regulation of pain perception. Furthermore, they seem to be relevant for some neuroendocrine processes. Their relevance in symptoms of schizophrenic psychoses seems to be more doubtful. In opiate dependence no significant alterations of endorphin concentrations could be observed as yet.
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PMID:[On the physiology and pharmacology of endorphins (author's transl)]. 22 45

beta-Endorphin is a 31 amino acid polypeptide isolated from the pituitary gland of different species of animals. It has strong morphine-like activity. It is formed of amino acid residues 61-91 of beta-lipotropin. Speculation has arisen whether it is biosynthesized in situ or transformed after secretion of beta-lipotropin. The present in vitro studies show that it is found as beta-endorphin in bovine pituitary slices incubated with radioactive amino acid precursor [35S]methionine. Chemical characterization and microsequencing of the newly biosynthesized material proves its identity with isolated unlabeled beta-endorphin and shows that it has a methionine residue at its fifth position, as expected.
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PMID:In vitro biosynthesis of beta-endorphin in pituitary glands. 26 82

The ontogenesis of cells containing polypeptide hormones (ACTH, MSH, LPH, GH and Prolactin) was investigated in the fetal rat hypophysis by immunohistochemistry using the peroxidase-antiperoxidase complex. Corticotrophs, melanotrophs and lipotropic cells were revealed earlier in the pars distalis than in the pars intermedia. In the pars distalis, cells producing LPH were found in the morning of day 15 of gestation using anti-gamma- or anti-beta-LPH sera, and in afternoon using anti-alpha- or beta-endorphin sera. Cells containing beta-MSH were observed from the afternoon of day 15. The cells stainable with the anti-alpha-MSH, anti-beta-(17--39)ACTH and anti-beta-(1--24)ACTH sera appeared on day 16. In the pars intermedia, the cells producing alpha-MSH, beta-MSH, alpha- and beta-endorphin, gamma- and beta-LPH were observed in the morning of day 17, while cells containing ACTH were only revealed in the afternoon of the same day of gestation. Based on the treatment of serial paraffin sections with various antisera, it was clearly shown that MSH, ACTH, and LPH occur in the same cells located in the pars distalis as in the pars intermedia. The development of the corticotrophs, melanotrophs and lipotropic cells does not require the presence of the fetal hypothalamus or other central nervous structures. The pituitary glands of 21 day-old fetus encephalectomized on day 16 showed as many reactive cells as those of the littermate controls. The somatotrophs were first revealed in the pars distalis in the afternoon of day 19. The cells producing prolactin were not observed before day 21 of gestation. On some cases GH and prolactin were found together in one cell. The cytodifferentiation of GH and prolactin cells is apparently not under hypothalamic control.
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PMID:Ontogenesis of cells producing polypeptide hormones (ACTH, MSH, LPH, GH, prolactin) in the fetal hypophysis of the rat: influence of the hypothalamus. 37 82

The molecule beta-lipotropin, composed of 91 amino acids (beta-LPH 1-91) has gained considerable importance in recent years. Its double role as the precursor of beta-MSH (beta-LPH 41-58) and beta-endorphin (beta-LPH 61-91) makes this peptide unique in its kind. Results are presented on the role of this molecule and on the complete characterization of two morphine-like peptides from human and sheep pituitaries. The structure-activity relationship of opiate activity is analyzed by scanning for this biological activity of many tryptic and CNBr fragments of beta-lipotropin. The unequivocal localization of one of the important synthesis sites of beta-endorphin in the pituitary neurointermediate lobe is presented. A peptide with partial sequence Met1, Leu8,15 and Lys6,11, 27, 29, 33 has been biosynthesized in large quantities and its ubiquitous nature and conservation of sequence speaks for its importance and possible presence in many living cells. This polypeptide was subsequently identified as ubiquitin, a non-histone fragment of the nuclear protein A-24.
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PMID:Beta-lipotropin precursor of beta-MSH and beta-endorphin. 38 58

The distribution of peptide hormone-like immunostaining in the gastrointestinal tract of 11 teleost species was investigated by immunofluorescence. Cells immunoreactive for somatostatin were found in the glandular epithelium of the stomach of four species and in the epithelium of the pyloric appendage of one species. The mid-gut epithelium contained cells reactive with antibodies to glucagon (three species), gastrin (five species), pancreatic polypeptide (five species), and substance P (two species). Cells immunoreactive for met-enkephalin were found in the epithelium of both the mid-gut and the stomach of six species. In six species in which the endocrine pancreas was investigated, insulin-, glucagon-, and somatostatin-like immunoreactivity was observed. Pancreatic polypeptide was definitely localised by immunostaining in cells of the endocrine pancreas of only one out of three species examined. Vasocative intestinal polypeptide-, neurotensin-, bombesin-, and enkephalin-like immunoreactivity was identified in the gastrointestinal nerve fibres in various species. In view of the considerable species variation found, caution should be exercised in generalising about the peptides present in the gastrointestinal tract of fish.
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PMID:Peptide hormone-like immunoreactivity in the gastrointestinal tract and endocrine pancreas of eleven teleost species. 38 3

Complementing cytochemical and ultrastructural studies, immunocytochemistry may be used to define, in terms of immunoreactivity, the nature of the polypeptide(s) made and stored in the cells of the endocrine pancreas, islet or otherwise. Immunoserums are applied to histological sections after fixation of the material in Bouin's fluid, and in accordance with four protocols: indirect immunofluorescence, immuno-enzymatic technique, variants in prolonged primary incubation and the method of soluble peroxidase-antiperoxidase complexes. Certain precautions are essential for correct interpretation. In the adult, four essential immunoreactions, corresponding to hormones or "local hormones" are regularly detected:insulin, pancreatic glucagon, somatostatin, pancreatic polypeptide. The cytochemical and ultrastructural characteristics of the cells involved are known (B, A and D cells for the first three specificities). C-peptide immunoreactivity is easily identified, but other immunoreactivities are more irregular or contested: gastrin, cholecystokinin, vasoactive intestinal peptide, ACTH, met-enkephalin.
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PMID:[Practical immunocytochemistry of the endocrine pancreas]. 39 37


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