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)

Growth hormone-releasing factor (GRF), a linear peptide that exists in a number of different molecular forms (GRF-44, -40, -37, and-31) has been shown to be responsible for the acromegaly associated with certain endocrine tumors of the pancreas and other foregut-derived structures. With the use of two anti-sera (#1A850 and G59/901) directed against different segments of the GRF molecule, a series of 24 pancreatic and 35 gastrointestinal endocrine tumors, not associated with acromegaly, were surveyed systematically for immunocytochemical localization of GRF in the tumor cells. Strong immunoreactivity for GRF was encountered in 10 tumors (6 pancreatic and 4 gastrointestinal). While all ten tumors were immunoreactive against G59/901, which recognizes GRF-44, -40, and -37, two jejunal carcinoids showed additional immunostaining with 1A850 that is specific for GRF-44. Seven of these ten tumors were also immunoreactive for a variety of other regulatory peptides and neurotransmitters, including gastrin, insulin, glucagon, serotonin, substance P, somatostatin, pancreatic polypeptide, vasoactive intestinal peptide (VIP), and adrenocorticotropic hormone (ACTH). No consistent pattern of association between GRF and the other regulatory substances was evident. These findings indicate that, even in the absence of associated acromegaly, up to 17% of endocrine tumors of the gastro-entero-pancreatic (GEP) axis show immunoreactivity for GRF and that such reactivity is associated more frequently with pancreatic (25%) than with gastrointestinal (11%) endocrine tumors.
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PMID:Immunocytochemical demonstration of growth hormone-releasing factor in gastrointestinal and pancreatic endocrine tumors. 300 Jan 64

Antibodies recognizing the 29-37 sequence of the human somatocrinin specifically stain a large population of interneurones located in the lateral dorsal hypothalamus. Staining comparisons revealed that these perikarya also contain alpha-MSH-like immunoreactivity. The neurones exhibiting human GRF1-37-like immunoreactivity correspond to the system previously shown to present alpha-MSH-like and rat CRF-like immunoreactivities.
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PMID:Coexpression of human growth hormone-releasing factor 1-37-like and alpha-melanotropin-like immunoreactivities in neurones of the rat lateral dorsal hypothalamus. 308 97

Passive immunization of rats with an antiserum raised against rat growth hormone-releasing factor (GRF) completely inhibited the growth hormone (GH) response to morphine and beta-endorphin but did not alter the prolactin (PRL) response to those two stimuli. These results demonstrate that opiate and opioid peptide stimulation of pituitary GH secretion is mediated through hypothalamic GRF and presents an animal model in which the stimulated secretion of GH and PRL can be specifically dissociated.
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PMID:Pituitary secretion of growth hormone in response to opioid peptides and opiates is mediated through growth hormone-releasing factor. 316 Sep 62

Recent data on the immunolocalization of regulatory peptides and related propeptide sequences in endocrine cells and tumors of the gastrointestinal tract, pancreas, lung, thyroid, pituitary (ACTH and opioids), adrenals and paraganglia have been revised and discussed. Gastrin, xenopsin, cholecystokinin (CCK), somatostatin, motilin, secretin, GIP (gastric inhibitory polypeptide), neurotensin, glicentin/glucagon-37 and PYY (peptide tyrosine tyrosine) are the main products of gastrointestinal endocrine cells; glucagon, CRF (corticotropin releasing factor), somatostatin, PP (pancreatic polypeptide) and GRF (growth hormone releasing factor), in addition to insulin, are produced in pancreatic islet cells; bombesin-related peptides are the main markers of pulmonary endocrine cells; calcitonin and CGRP (calcitonin gene-related peptide) occur in thyroid and extrathyroid C cells; ACTH and endorphins in anterior and intermediate lobe pituitary cells, alpha-MSH and CLIP (corticotropin-like intermediate lobe peptide) in intermediate lobe cells; met- and leu-enkephalins and related peptides in adrenal medullary and paraganglionic cells as well as in some gut (enterochromaffin) cells; NPY (neuropeptide Y) in adrenaline-type adrenal medullary cells, etc.. Both tissue-appropriate and tissue-inappropriate regulatory peptides are produced by endocrine tumours, with inappropriate peptides mostly produced by malignant tumours.
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PMID:Endocrine cells producing regulatory peptides. 329 70

Centrally administered neuropeptides were investigated for their effects on the development of gastric lesions in rats. Thyrotropin releasing hormone (TRH), vasoactive intestinal peptide (VIP) and gonadotropin releasing hormone (LHRH) produced gastric lesions acutely, with TRH demonstrating the most pronounced effect in terms of incidence and severity. Ten-fold higher doses of the same peptides administered intravenously produced none or very few gastric lesions. Moreover, pretreatment with atropine partially inhibited their production. Corticotropin releasing factor (CRF) exhibited only mild ulcerogenic effects, and the gastric lesions induced with this peptide developed more slowly than with TRH, VIP and LHRH. Although ulcerogenic in their own right, none of these four neuropeptides significantly potentiated the potent ulcerogenic effects of cold-restraint stress. Since other neuropeptides, including somatostatin, human pancreatic growth hormone releasing factor (hpGRF), substance P, bombesin, and neurotensin, had no demonstrable effects on gastric mucosa, we can conclude that the lesions were not a general effect of intracisternal administration of neuropeptides. The results suggest that within the central nervous system, there are several neuropeptides that play a significant role in the development of gastric lesions via, at least in part, vagal-dependent mechanisms.
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PMID:The effects of centrally administered neuropeptides on the development of gastric lesions in the rat. 392 Apr 62

By specialized cell types of the hypothalamus 6 peptides (liberins) acting stimulating on the synthesis and secretion of hormones of the pituitary gland and 3 peptides acting inhibiting (statins) were formed. The synthesis of the hypothalamus hormones apparently takes place from larger precursor molecules. Under influence of corticoliberin the pro-opiomelanocortin is formed in the pituitary gland, the breaking up of which produces in the anterior pituitary lobe the ACTH, the beta-lipotropin and the beta-endorphin as well as in the middle lobe above all melanotropins. The secretion of the growth hormone is furthered above all by the somatoliberin and inhibited by the somatostatin. The luliberin stimulates the secretion of follicle stimulating hormone (FSH) and the luteinising hormone (LH). In increased secretion of prolactin the supply of the FSH- and LH-synthetizing cells with receptors for the luliberin is decreased. The secretion of the prolactin is furthered by the prolactoliberin and inhibited by the prolactostatin. In the regulation of the release of the melanotropins also participate 2 peptides. In the adrenal cortex the melanotropins further the synthesis of glucocorticosteroids stimulated by ACTH.
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PMID:[Current knowledge on the biochemistry and function of hypothalamic hormones]. 613 22

Human GRF-(1-44)-NH2 (GRF-44) was administered iv in graded doses of 0.01-10 micrograms/kg to 35 normal young adult men and 38 women. GRF-44 stimulated the release of GH in a dose-dependent fashion, although the individual responses varied widely. The ED50 values for this effect were 0.4 micrograms/kg in men and 0.2 micrograms/kg in women in the midfollicular phase of the menstrual cycle. Maximal responses in men and women were not significantly different, and a dose of 1 micrograms/kg was sufficient to produce a maximal response. There was, likewise, no difference between responses of women tested in the midfollicular and midluteal phases of the cycle. There were no changes in PRL, LH, FSH, TSH, ACTH, beta-endorphin, or cortisol at doses up to 1 microgram/kg; at 10 micrograms/kg, PRL increased by an average of 7.6 ng/ml in the women. Side effects occurred in approximately 20% of both men and women at 1 microgram/kg and in nearly all subjects given 10 micrograms/kg; these consisted primarily of flushing and a sense of warmth. Thus, a dose of 1 microgram/kg GRF-44 is safe and effective, and would appear to be a reasonable choice for use in studying GH responses in normal subjects of other ages and in patients with disorders of GH secretion.
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PMID:Dose-response relationships for the effects of growth hormone-releasing factor-(1-44)-NH2 in young adult men and women. 633 Jan 51

The hypophysiotropic activities of a synthetic human pancreatic growth hormone releasing factor (hpGRF) with 40 residues was examined in vitro using rat pituitary halves. At concentrations from 10(-10) M to 10(-7) M the peptide stimulated GH release in a dose-dependent manner with the ED50 being 1.2 x 10(-9) M. The concentration of 10(-10) M hpGRF is comparable to the basal hypophyseal portal blood levels of other known hypothalamic hypophysiotropic hormones. However, GH release was enhanced three-fold by concentration as low as 10(-12) M, though no dose-response relationship was observed up to 10(-10) M. Thus, this peptide not only stimulates the release of GH in a dose-dependent manner, but at lower concentrations also maintains elevated GH levels. The release of ACTH, beta-endorphin, LH, and FSH was not affected by hpGRF at any of the concentrations tested. At hpGRF concentrations less than 10(-7) M, the release of TSH and PRL were unaffected. However, at 10(-6) M, TSH release was enhanced about 2.5 fold and prolactin release was elevated slightly.
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PMID:In vitro pituitary hormone releasing activity of 40 residue human pancreatic tumor growth hormone releasing factor. 640 22

Preliminary observations [Sykes & Lowry (1980) J. Endocrinol. 85, 42P-43P] had suggested that the major hypothalamic somatoliberin (growth-hormone-releasing factor) was a larger peptide than the other characterized hypothalamic factors, with an elution position on Sephadex G-50 between those of neurophysin and corticotropin. The present paper reports the isolation and preliminary characterization of pig hypothalamic somatoliberin. Acid extracts of pig stalk median eminence were purified by gel filtration and preparative and analytical high-pressure liquid chromatography to yield a preparation that was specific in the release of somatotropin (growth hormone) in vitro, giving a steep dose--response curve at doses in the range 0.20-3.0 ng. Amino acid analysis revealed a non-cysteine-containing peptide with a high number of glutamate (or glutamine) and aspartate (or asparagine) residues. The peptide had about 56-57 amino acid residues and an apparent molecular weight of 6400, in keeping with its elution position on a column of Sephadex G-50.
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PMID:Purification of a high-molecular-weight somatoliberin (growth-hormone-releasing factor) from pig hypothalami. 640 74

alpha-MSH and other fragments of ACTH are potent stimulators of GH release in vivo. The action of such peptides and of extracts of the neurointermediary lobe (NIL) of rat pituitary, a source of endogenous MSH-related peptides, on GH release was investigated in vitro. Peptides with the core sequence of alpha-MSH stimulate GH secretion by primary cultures of rat anterior pituitary cells; however, both the absolute and the relative potencies of these peptides exclude the involvement of melanotropic receptors comparable in specificity to the extrapituitary receptors for these hormones. Extracts of the NIL of rat pituitary stimulate GH release in vitro and the bulk of the releasing activity can be attributed to one (or several) factors with an apparent mass of approx. 10 000 M.W. that can be partially purified by HPLC. The active principle appears to be distinct from both beta-LPH and the human pancreatic GHRF. Thus, while rat NIL contains GH-releasing activity that can be demonstrated in vitro, a direct link to the potent action of MSH-related peptides on GH release in vivo cannot be established, and the action of these peptides in vivo must therefore rely on mechanisms which are not expressed in the in vitro system.
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PMID:Peptides of the neurointermediary lobe of rat pituitary stimulate GH secretion in vitro. 641 59


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