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 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 stimulation of lipolysis in isolated rat and rabbit fat cells by adrenocorticotropin (ACTH) and alpha-melanotropin has been studied. The concentration of alpha-melanotropin required for half maximal stimulation is 0.23 times that of ACTH in rabbit adipocytes but as high as 1140 times that of ACTH in rat fat cells. Chemical modification of the tryptophan residue in ACTH and melanotropin resulted in a loss of lipolytic activity in rat adipocytes and an increase in lipolytic potency in rabbit fat cells. These differences between rat and rabbit fat cells were evident when stimulation of cyclic AMP synthesis was measured in isolated cells or ghosts. The results are discussed in terms of the difference in the hormone receptors of the fat cells of the two species.
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PMID:Divergent effects of adrenocorticotropin and melanotropin on isolated rat and rabbit adipocytes. 17 69

The ability of alpha-melanotropin and a series of synthetic peptides related to adrenocorticotropin (ACTH) to stimulate steroidogenesis in isolated rat adrenal cells, melanin dispersion in frog melanophores and lipolysis in rat and rabbit fat cells have been studied. It was found that the steroidogenic activity closely paralleled the lipolytic activity of these peptides in rat fat cells, whereas the melanocyte stimulating activity paralleled the lipolytic activity in rabbit fat cells. These results indicate that the structural requirements for stimulating steroidogenesis in isolated rat adrenal cells and lipolysis in isolated rat fat cells are quite similar. The structural features required for eliciting lipolysis in rabbit fat cells appear to be very similar to those necessary for stimulating frog melanophores. The possibility that regulation of lipid metabolism in the rabbit may be a new function acquired by melanotropin is discussed.
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PMID:Comparison of the steroidogenic and melanotropic activities of corticotropin, alpha-melanotropin and analogs with their lipolytic activities in rat and rabbit adipocytes. 17 70

Swine adipose tissue was not responsive to glucagon at any age and only marginally to adrenocorticotropin (ACTH). The latter response could be greatly magnified and the sensitivity increased by addition of theophylline (Theo). The maximal lipolytic activity (MAX) obtained with ACTH plus Theo was minimal in the newborn, greatly increased in young animals, and reduced during the growing period; however, the sensitivity did not change. The MAX for Theo (plus low epinephrine) yielded a pattern similar to ACTH, but the sensitivity changed (most sensitive in younger animals). The MAX and sensitivity obtained with dibutyryl cyclic adenosine monophosphate were not appreciably changed during development.
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PMID:Factors influencing the lipolytic response of swine (Sus domesticus) adipose tissue: ontogeny. 17 22

Alpha-MSH, beta-MSH and ACTH have been localized in the cells of hypophyseal intermediate lobe by fluorescence histoimmunological technics. Elaboration and excretion of these polypeptides are enhanced after dehydration or adrenalectomy. The most evident variations are seen with alpha-MSH and ACTH after dehydration, with beta-MSH after adrenalectomy.
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PMID:Immunohistochemical study of the pars intermediate of the mouse pituitary in different experimental conditions. 17 45

Isoproterenol, corticotropin (ACTH), and triodothyronine immobilized on glass and Sepharose beads by diazotization procedures have been shown to interact with cultured tumor cells of "target tissue" origin. Cells used were rat glioma cells (C6), rat adrenal tumor cells (Y-1), and rat pituitary tumor cells (GH3). The rat glioma cells bound principally to immobilized isoproterenol, whereas the rat adrenal tumor cells bound to immobilized corticotropin, and rat pituitary tumor cells bound to immobilized triiodothyronine. Binding was inhibited by preincubation of the cells in soluble drug or hormone. With C6 cells there was a positive correlation between adenylate cyclase [ATP pyrophosphate-lyase (cyclizing, EC 4.6.1.1] stimulation and the degree of binding to the immobilized isoproterenol. Norepinephrine, bound through the ethanolamine side chain via an amide linkage, did not bind cells, demonstrating specific structural requirements for drug-cell interactions. HeLa cells were shown to bind tightly to diphtheria toxin coupled to Sepharose beads via an amide bond. This binding was inhibited by prior incubation of the Sepharose toxin with purified antitoxin. Toxin bound to Sepharose via an azo bond did not bind cells. These data suggest that the cell affinities are due to cell surface receptors interacting with the immobilized drugs and hormones, and that the observed affinities possibly reflect the relative receptor complement of these cells.
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PMID:Affinity isolation of cultured tumor cells by means of drugs and hormones covalently bound to glass and Sepharose beads. 18 May 34

To investigate whether the hypothalamus is involved in the cytodifferentiation of the anterior pituitary gland, rat foetuses were encephalectomized in utero on day 16 of pregnancy. Pituitary sections from encephalectomized and normal littermate foetuses were studied on day 21 with the immunofluorescence technique using antibodies anti alpha-MSH, anti beta-MSH, anti alpha-(17-39) ACTH and anti beta-(1-24) ACTH. On day 16, only the anti beta-MSH revealed a few cells in the pars distalis but not in the pars intermedia. On the other hand, on day 21, the pituitary cells reacting with antibodies anti alpha-MSH, anti beta-MSH and anti alpha-(17-39) ACTH were as numerous in the encephalectomized foetuses as in the normal littermate foetuses. The cells revealed with the antibody anti beta-(1-24) ACTH were less numerous and less fluorescent in the pars distalis and intermedia of the hypophysis of the encephalectomized foetuses. On day 21, the adrenals of the encephalectomized foetuses were atrophied in comparison with those of the normal littermate foetuses but they were larger than on day 16. These data suggest that the cytodifferentiation of the corticotroph and melanotroph cells of the hypophysis occurs without the influence of the hypothalamus which is necessary for the normal release of ACTH.
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PMID:Hypothalamus and cytodifferentiation of the foetal pituitary gland. Study in vivo. 18 Nov 34

Big corticotropin (adrenocroticotropic hormone, ACTH), an immunoreactive form of ACTH with low biological activity and which elutes in the void volume on Sephadex G-50 gel filtration, is found in plasma and extracts of human pituitary and tumour. Controlled tryptic digestion of big ACTH releases a product with full corticotropic activity which is indistinguishable from the (1-39) ACTH with respect to size, charge and susceptibility to tryptic digestion. Immunoreactive ACTH, predominantly in the big form, is found in virtually all tissue extracts of carcinoma primary to or metastatic from the lung, but not of carcinoma metastatic to the lung, and even in precancerous lung lesions. The absence of clinical Cushing syndrome in patients with carcinoma of the lung and moderate elevation of plasma concentrations of ACTH is due to the low biological activity of big ACTH. Prolonged survival (for more than two years) of patients with lung carcinoma has been observed only in those whose plasma ACTH is low before therapy or after resection of the lung tumour. Rabbit, rat and mouse pituitaries contain an intermediate sized ACTH but the usual 1-39 peptide predominates in the pituitaries of monkey, sheep, dog, cat and guinea pig, as well as man. The hormonal form of ACTH appears to be an important factor regulating the cortisol/corticosterone ratio in mammalian adrenal corticoid secretion because administration of porcine ACTH to rabbits alters the adrenal secretory pattern so as to decrease corticosterone production and increase cortisol production.
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PMID:Multiple forms of corticotropin (adrenocorticotropic hormone, ACTH) and their significance. 18 Dec 23

Adrenocorticotropic hormone (ACTH) concentrations in umbilical arterial and venous plasma were measured in newborn infants delivered both vaginally and by cesarean section. Mean ACTH was significantly higher in the arterial (602.0 pg. per milliliter) than venous (261.5 pg. per milliliter) plasma in vaginal deliveries (pless than 0.01). Arterial plasma of babies born by elective cesarean section before initiation of labor contained less ACTH (384.7 pg. per milliliter) when compared to those delivered after labor had started (698.7 pg. per milliliter). Serial determinations of ACTH in pooled fetal blood obtained during labor showed that the average hormone titers increased significantly from first stage (295.2 pg. per milliliter) to second stage of labor (440.5 pg. per milliliter), and reached a peak at delivery (645.4 pg. per milliliter). The pituitary gland of the fetus at midtrimester contained ACTH. Possible mechanisms for fetal secretion of ACTH at delivery are discussed.
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PMID:Adrenocorticotropic hormone in human fetal blood at delivery. 18 91

Circular dichroism spectra on corticotropin1-32 and its constitutive N-, and C-terminal peptides are determined in water and trifluoroethanol under several conditions in the aromatic and peptide spectral regions. Furthermore, the effects of pH and varied mixtures of water-trifluoroethanol are examined on the corticotropin1-32 molecule. The results show that the N- and C-terminal series have a different behaviour in both aqueous and organic media. Corticotropin and the former peptides display "random" spectra in water, and alpha-helix type spectra in trifluoroethanol, while the latter have "random" spectra in both solvents. In the holopeptide corticotropin, the side chain-side chain effects, as reflected by the titration curves obtained from variations in the aromatic region, support the idea of an helical organization of part of the backbone even in aqueous solution. When going from water to trifluoroethanol corticotropin1-32 undergoes a conformational change which leads to an alpha-helix, following a linear pathway. These results, together with other observations, indicate the possible role of the conformation of corticotropin molecules in their biological life.
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PMID:Conformational studies of corticotropin1-32 and constitutive peptides by circular dichroism. 18 36


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