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)

Using a specific radioimmunoassay for gamma-MSH, a predicted peptide in the cryptic N-terminal portion of the adrenocorticotropin-beta-lipotropin precursor, gamma-MSH-like immunoreactivity (gamma-MLI) was detected in two ectopic ACTH producing tumors. Gel chromatographic studies on Bio-Gel P-60 revealed one or two peaks of gamma-MLI; one was eluted near th elution position of beta-LPH, compatible with gamma-MLI in human pituitary and the other emerged near the position of beta-endorphin. These results indicate that ectopic ACTH-producing tumors eleborate not only ACTH, beta-endorphin but also gamma-MLI.
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PMID:Evidence for gamma-MSH-like immunoreactivity in ectopic ACTH-producing tumors. 624 46

Beta-Endorphin and ACTH immunoassays were employed to examine the concentrations, distributions, and character of those peptides in rat gastrointestinal tissues. Sections of the gastrointestinal tract were obtained from fasted and fed animals and were extracted in 5 N acetic acid containing proteolytic enzyme inhibitors. Aliquots immunoassayed for beta-enddorphin and ACTH revealed highest concentrations to be present in the small bowel, with stomach and colon containing little immunoreactivity. Tissues from fasted animals contained more immunoreactivity than did those from fed animals. Gel chromatography showed the presence of large molecular weight forms of beta-endorphin and ACTH in gut extracts. Concanavalin A affinity chromatography revealed that approximately 5% of gut immunoreactivity contained carbohydrate. Therefore, beta-enddorphin and ACTH immunoreactivities are present im the gut. The demonstration of large molecular weight and glycosylated forms of immunoreactivity suggests the presence of biosynthetic precursors of beta-endorphin and ACTH. The increase in immunoreactivity in response to fasting suggests that these peptides play a role in gut physiology.
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PMID:Beta-endorphin and adrenocorticotropin in extrapituitary sites: gastrointestinal tract. 624 23

Using a specific radioimmunoassay for gamma-melanotropin (gamma-MSH), one of the predicted fragments in the amino-terminal portion of the adrenocorticotropin(ACTH)-beta-lipotropin (beta-LPH) precursor, gamma-MSH-like immunoreactivity (gamma-MSH-LI) was detected in human plasma from 4 of 5 patients with Addison's disease and 2 of 3 patients with Nelson's syndrome. None of the normal subjects or patients with Cushing's disease showed detectable concentrations (more than 150 pg/ml) of gamma-MSH-LI. gamma-MSH-LI was secreted concomitantly with ACTH-like immunoreactivity (ACTH-LI) and beta-endorphin-like immunoreactivity (beta-endorphin-LI) in response to insulin-induced hypoglycemia and the administration of lysine-vasopressin. Conversely, intravenous injection of cortisol lowered plasma concentrations of gamma-MSH-LI concomitantly with those of ACTH-LI and beta-endorphin-LI. Gel chromatographic studies of the plasma extracts showed a single peak of gamma-MSH-LI near the elution position of human beta-LPH. These results suggest that gamma-MSH-LI in human plasma is present as a big form and that this big gamma-MSH is secreted concomitantly with ACTH and beta-endorphin.
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PMID:Concomitant secretion of Y-MSH with ACTH and beta-endorphin in humans. 625 36

To elucidate the significance of beta-endorphin in human cerebrospinal fluid (CSF), CSF levels of beta-endorphin-like immunoreactivity (beta-EP-LI) in various diseases were determined by a specific radioimmunoassay and compared with simultaneously determined ACTH-like immunoreactivity (ACTH-LI) levels in CSF. CSF beta-EP-LI and ACTH-LI in the control group, consisting of 5 normal subjects and 19 patients with nonendocrine diseases, were 22.2+/-1.3 and 14.6+/-0.4 fmol/ml, respectively. CSF levels of these peptides in patients with schizophrenia (n = 19) and acromegaly (n = 10) were not significantly different from those in the control group. Patients with Cushing's disease (n = 7) had significantly lower CSF beta-EP-LI and ACTH-LI levels than those in the control group. Four of them showed a parallel increase in CSF beta-EP-LI and CSF ACTH-LI levels after the complete removal of pituitary microadenomas (P < 0.05). Gel chromatography of CSF beta-EP-LI from a normal volunteer, a control patient, and one patient each with catatonia, Nelson's syndrome, Cushing's syndrome (adrenal adenoma), and acromegaly gave similar patterns consisting of three peaks with the elution positions comparable to those of authentic beta-endorphin, beta-lipotropin, and possibly their precursor molecule. Gel chromatographic patterns of CSF beta-EP-LI and ACTH-LI were compared in a normal volunteer. The first peaks of beta-EP-LI and ACTH-LI eluted at the same position and the second peak of ACTH-LI coincided with the elution position of authentic ACTH.CSF beta-EP-LI and ACTH-LI levels determined every 5 min over a period of 80 min in three normal volunteers did not show moment-to-moment variability.A significant correlation (r = 0.75, P < 0.001) was seen between CSF beta-EP-LI and ACTH-LI levels in normal subjects and patients studied (n = 73). This suggests that beta-endorphin and ACTH in human CSF share the common regulatory mechanism in normal and pathologic conditions.
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PMID:Immunoreactive beta-endorphin and adrenocorticotropin in human cerebrospinal fluid. 625 11

Regulation of secretion of ACTH-, beta-endorphin-, and gamma-melanotropin-like immunoreactivities (ACTH-LI, beta-EP-LI, and gamma-MSH-LI, respectively) was studied by using a perfused Sephadex column containing dispersed pituitary tumor cells obtained from three patients with Cushing's disease. Serial dilution of the perfusion medium gave lines parallel to the standard curve in each RIA for ACTH, beta-EP and gamma-MSH, suggesting that immunoreactive materials in the medium are immunologically indistinguishable from the authentic peptides. Gel exclusion chromatography of the medium revealed the existence of ACTH, beta-lipotropin (beta-LPH), beta-EP, and their possible precursor protein. gamma-MSH-LI consists of a major peak of big gamma-MSH eluted near the elution position of beta-LPH, suggesting the entire or nearly entire N-terminal portion of the precursor molecule. The addition of lysine vasopressin and rat median eminence extracts (MEE) to the perfusion system concomitantly enhanced the release of ACTH-LI, beta-EP-LI, and gamma-MSH-LI, although the dose-response relationship was clear-cut only in the case of MEE. TRH and LRH also elicited the concomitant release of these peptides in one patient, in whom combined administration of TRH and LRH significantly augmented plasma cortisol levels when studied preoperatively. The molar ratio of ACTH-LI to beta-EP-LI was approximately 1.0, whereas gamma-MSH-LI was about one fourth of ACTH-LI when compared on a weight basis. These results indicate that 1) ACTH-producing human pituitary adenomas concomitantly secrete ACTH, beta-LPH, beta-EP, and big gamma-MSH, and 2) lysine vasopressin, MEE, TRH, and LRH act directly on pituitary cells to stimulate the release of these peptides.
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PMID:Concomitant secretion of adrenocorticotropin, beta-endorphin, and gamma-melanotropin from perfused pituitary tumor cells of Cushing's disease: effects of lysine vasopressin, rat median eminence extracts, thyrotropin-releasing hormone, and luteinizing hormone-releasing hormone. 625 4

Immunoreactive (IR)-gamma 3-melanotropin (MSH), -adrenocorticotropin (ACTH) and -beta-endorphin in various areas of bovine brain were measured with their respective radioimmunoassays (RIA). The concentrations of IR-gamma 3-MSH were almost the same as those of IR-ACTH in most areas. Furthermore, in all brain regions, the concentrations of both peptides were lower than those of IR-beta-endorphin. The highest concentration of IR-gamma 3-MSH was found in hypothalamus, followed by thalamus, midbrain and striatum. Gel permeation chromatographic studies showed that the main gamma 3-MSH-like peptide in the hypothalamus, striatum and midbrain was a small form, whose molecular weight is about 4500. These brain gamma 3-MSH-like peptides were also found to be glycosylated.
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PMID:The regional distribution of gamma 3-melanotropin-like peptides in bovine brain is correlated with adrenocorticotropin immunoreactivity but not with beta-endorphin. 626 81

Clonidine (10(-6), 10(-7) M) evokes the release of beta endorphin-like immunoreactivity (beta-END-LI) from cell cultures of anterior (pars distalis) but not neurointermediate (pars nervosa plus pars intermedia) lobe of the rat pituitary. This drug-induced secretion is blocked by alpha-adrenergic (phenoxybenzamine, yohimbine; 10(-5) M) but not beta-adrenergic (propranolol, 10(-5) M) antagonism. Gel filtration (Sephadex G-50) reveals that beta-END-LI released from anterior lobe cells consists of 2 major forms of immunoreactivity which coelute with beta-lipotropin or beta-endorphin standards. Conversely, beta-END-LI released spontaneously from neurointermediate lobe cells almost entirely corresponds to beta-endorphin. The data show that alpha-adrenergic stimulation by clonidine releases beta-END-LI selectively from cells of anterior but not neurointermediate lobe in vitro and suggests that the clonidine-induced release of pituitary beta-END-LI we have observed in vivo occurs in part by direct action on the corticotrophs of the pars distalis.
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PMID:Clonidine releases immunoreactive beta-endorphin from rat para distalis. 626 93

Using gel exclusion chromatography on Bio-Gel P-60, gamma-melanotropin-like immunoreactivity (gamma-MSH-LI) in three human pituitary glands, two ACTH-producing pituitary adenomas, and three ectopic ACTH-producing tumours (two medullary thyroid carcinomas and one thymoma) was divided into one or two molecular weight classes. The largest component eluted near the position of mouse 16K fragment and was designated big gamma-MSH-LI. This big gamma-MSH-LI was present in all samples. The second one, designated intermediate gamma-MSH-LI, eluted between the position of mouse 16K fragment and human ACTH, and was demonstrated only in two ectopic ACTH-producing tumours. No gamma-MSH-LI emerged at the elution position of synthetic gamma 3-MSH. Affinity chromatography on concanavalin A-agarose revealed that a significant fraction (52-68%) of gamma-MSH-LI from human pituitary glands, ACTH-producing pituitary adenomas, and one ectopic ACTH-producing tumour bound to the column and was eluted with alpha-methyl-D-mannopyranoside. In two ectopic ACTH-producing tumours which contained big and intermediate gamma-MSH-LI, a relatively small fraction (27-35%) of gamma-MSH-LI bound to the column and was similarly eluted. These observations suggest that human gamma-MSH-LI is glycosylated and that there is an abnormality in the glycosylation of gamma-MSH-LI in some ectopic ACTH-producing tumours.
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PMID:Gamma-melanotrophin-like immunoreactivities in human pituitaries, ACTH-producing pituitary adenomas, and ectopic ACTH-producing tumours: evidence for an abnormality in glycosylation in ectopic ACTH-producing tumours. 627 45

gamma MSH-like, ACTH-like, and beta-endorphin-like immunoreactivities (gamma MSH-LI, ACTH-LI, and beta-endorphin-LI, respectively) were detected in water extracts of four human gastric antral mucosa. The concentrations of gamma MSH-LI, ACTH-LI, and beta-endorphin-LI in the boiling water extracts were 9.9 +/- 3.3, 6.2 +/- 1.8, and 3.9 +/- 1.3 ng/g (mean +/- SE), respectively. Gel exclusion chromatography on a Bio-Gel P-60 column showed that most ACTH-LI and beta-endorphin-LI were eluted at the elution positions of human ACTH and beta-endorphin, respectively. The major peak of gamma MSH-LI was eluted at the elution position of big gamma MSH-LI, but another peak was eluted at the elution position of small gamma MSH-LI, as in bovine intermediate pituitary. Concanavalin A-agarose affinity chromatography showed that 52% of gamma MSH-LI was specifically bound to the column, but only 8% of ACTH-LI and none of beta-endorphin-LI were specifically bound. These results suggest that there exists an ACTH/beta-lipotropin common precursor protein in human antral mucosa and that the processing of the precursor is accelerated as a bovine intermediate pituitary, indicating possible roles of these peptides in the function of the gastrointestinal tract.
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PMID:Presence of immunoreactive gamma-melanocyte-stimulating hormone, adrenocorticotropin, and beta-endorphin in human gastric antral mucosa. 627 2

The distinctive chromatographic patterns of beta-endorphin-like immunoreactivity (beta END-LI) released from rat pars distalis (PD) or pars intermedia in vitro as well as the selective inhibitory effects of dexamethasone on PD were used to determine which lobe secretes beta END-LI into plasma after clonidine administration in vivo. Gel chromatography (Sephadex G-50) indicates that cultured PD cells released two major immunoreactive species which coelute with beta-lipotropin (beta LPH) or beta END standards. Conversely, virtually all of the beta END-LI secreted by neurointermediate lobe [pars intermedia plus pars nervosa (NIL)] cells in vitro resembled beta END in size, while none was detected which cochromatographed with beta LPH. Incubation of PD cells with clonidine (10(-6) M) evoked a 2-fold increase in beta END-LI release, while the drug had no effect on beta END-LI released from cultured NIL cells. Dexamethasone (10(-7) M) inhibited the clinidine-induced release of beta END-LI from PD cells, whereas it did not influence the stimulated release of beta END-LI from NIL by isoproterenol (10(-6) M). In vivo administration of clonidine (0.5 mg/kg, ip, for 15 min) increased total plasma beta END-LI from 0.75 +/- 0.16 to 1.35 +/- 0.18 ng/ml; 85% of this rise corresponded to beta LPH as determined by gel chromatography. Prior administration of dexamethasone (60 micrograms/kg, ip, for 4 h) completely prevented the clonidine-induced release of beta END-LI in vivo. These results demonstrate that clonidine probably acts selectively on the PD in vivo to release pituitary beta END-LI, and further, that PD can release beta END-LI independently of the pars intermedia.
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PMID:Evidence for independent secretion of beta-endorphin immunoreactivity from rat pars distalis in vivo. 627 37


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