Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01189 (beta-endorphin)
21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gel chromatographic, immunologic and biologic properties of beta-melanocyte-stimulating hormone (beta-MSH) in tumor tissues obtained from eight patients with the ectopic ACTH syndrome were studied and compared to those of pituitary beta-MSH. Size heterogeneity of immunoreactive beta-MSH was found in all the tumors studied as well as in normal human pituitaries. Both the tumors and pituitaries contained immunoreactive beta-MSH of a larger molecular size than the well-characterized beta-MSH of small molecular size. The large molecular weight beta-MSH also predominated in the plasma. It was found to be bioactive by an in vitro MSH assay, immunologically indistinguishable from human beta-MSH, and chromatographically very similar to beta-lipotropic hormone (beta-LPH). Tryptic digestion of the large molecular weight beta-MSH under controlled conditions promptly produced bioactive beta-MSH of small molecular size, followed by the appearance of immunologically active but biologically inert fragments. These results suggest that the ectopic ACTH-producing tumor as well as the pituitary elaborate beta-LPH-like peptide which might be the predominant component of immunoreactive beta-MSH in man.
...
PMID:Size heterogeneity of beta-MSH in ectopic ACTH-producing tumors: presence of beta-LPH-like peptide. 17 84

A continuous line (DMS-79) of human pulmonary small cell carcinoma cells was shown to secrete immunoreactive adrenocorticotropin (ACTH), lipotropin, and beta-endorphin concomitantly into the culture medium. Gel filtration of the culture medium demonstrated at least five components: high molecular weight material(s) that had ACTH, lipotropin, and beta-endorphin immunoreactivities and materials similar to ACTH, beta-lipotropin, gamma-lipotropin, and beta-endorphin in their immunoreactivities and apparent molecular weights. The same components were observed when gel filtration was carried out in 6 M guanidine-HCl, and the high molecular weight material(s) appeared to consist of more than one component, with molecular weights in the range of 15,000-40,000. Immune affinity chromatography of the high molecular weight component(s) from gel filtration with a specific anti-(1-24)ACTH serum demonstrated that the ACTH, lipotropin, and beta-endorphin immunoreactivities were possessed by the same molecule(s), suggesting that ACTH, lipotropins, and beta-endorphin were derived from a common, high molecular weight precursor.
...
PMID:Corticotropin, lipotropin, and beta-endorphin production by a human nonpituitary tumor in culture: evidence for a common precursor. 21 15

A human pituitary adenoma responsible for a case of Nelson's syndrome was maintained in organ culture and the incubation medium was examined with four different RIAs; human corticotropin (ACTH), beta-MSH, lipotropin (LPH), and beta-endorphin (beta-End). All four immunoreactivites (IRs) were present in the medium obtained after 24 h of incubation. Gel exclusion chromatography under denaturing conditions (6 m guanidine HCl) revealed several immunoreactive components. Two components having both human beta-MSH (beta-hMSH) and human LPH (hLPH) IR coeluted with beta-hLPH and gamma-hLPH; a component with beta-hMSH IR but no hLPH IR coeluted with [125I]beta-hMSH; a component with human ACTH (hACTH) IR eluted at the position of hACTH. Sephadex G-50 gel exclusion chromatography revealed that approximately 80% and 20% of human beta-End (beta-hEnd) IR were accounted for by components coeluting with beta-hLPH and beta-hEnd, respectively. These data demonstrate the presence in this incubation medium of materials similar to if not identical with beta-hLPH, gamma-hLPH, hACTH, beta-hMSH, and beta-hEnd; they suggest that all of these peptides may be secreted in the circulation of patients with Nelson's syndrome.
...
PMID:Characterization of lipotropin-, corticotropin-, and beta-endorphin-immunoreactive materials secreted in vitro by a human pituitary adenoma responsible for a case of Nelson's syndrome. 22 44

This study investigates the effect of pertubation of the normal pituitary-adrenal axis on concentrations of adrenocorticotropin (ACTH)-like immunoactivity in peripheral tissues. We used a polyclonal antibody (West antibody) to measure ACTH-like immunoactivity in glacial acetic acid extracts of five tissues in adult male rats at increasing times (1, 7, 14, and 28 days) after hypophysectomy or adrenalectomy, and in normal control rats. Concentrations of ACTH-like immunoactivity were similar to those previously reported in liver, colon, heart, and small intestine and were not significantly affected by either hypophysectomy or adrenalectomy. While hypophysectomy also had no effect in the kidney, adrenalectomy resulted in a four-fold increase in extractable immunoactivity, first noticeable at seven days (p less than 0.005), but increasing progressively to 28 days (p less than 0.0005). Gel filtration showed that most of the increase in activity in kidneys of adrenalectomized rats corresponded to the 4.5 kD form comprising most of the serum ACTH immunoactivity and suggesting that the activity increase in kidney was largely due to ACTH derived from blood.
...
PMID:ACTH immunoactivity in normal rat tissues: modulation by hypophysectomy and adrenalectomy. 131 81

The human placenta has been implicated as a source of numerous peptide hormones during pregnancy. Since the immunoassay detection of the proopiomelanocortin derived peptide beta-endorphin (beta E) in placental extracts in 1978, it has remained uncertain whether placental beta E immunoreactivity (IR) is 1) secreted into the maternal circulation and 2) opiate receptor active during pregnancy. To elucidate the nature of beta E IR in the placenta, both beta E IR and N-alpha-acetylated beta E (Ac beta E) IR were simultaneously measured in extracts of human pituitaries, placentas, and plasma by two homologous RIAs. Pituitary extracts (n = 6) contained 38 +/- 7 nmol beta E IR per g wet wt tissue (mean +/- SEM), of which only 20 +/- 4 pmol/g were Ac beta E IR. Term placental extracts (n = 19) had 201 +/- 30 fmol/g wet wt total beta E IR and 30 +/- 3 fmol/g wet wt total Ac beta E IR, which comprised 15% of total beta E IR in placental extracts. Total plasma beta E IR rose from 28 weeks gestation (8.5 +/- 0.3 fmol/mL, n = 159) to peak at labor (50 +/- 4 fmol/mL, n = 98; P < 0.01) but total Ac beta E IR was found in only four 28-week (1.7 +/- 0.9 fmol/mL) and 42 labor plasma samples (0.9 +/- 0.1 fmol/mL). Gel filtration chromatography of placental and pituitary extracts showed that while less than 1% of the beta E31-size material was acetylated in the pituitary, up to 60% of the beta E31-size material in placental extracts was acetylated. In pooled third trimester plasma extracts, however, only 4% of the beta E31-size material was acetylated. Furthermore, the ratio of beta E31:beta-lipotropin in pituitary extracts (n = 3) was 0.5; pooled plasma-0.5, and placental extracts (n = 5)-1.2. These data indicate that 1) the placenta extensively N-alpha-acetylates beta E31 destroying its opiate bioactivity while the pituitary does not; 2) beta E IR in pregnant women's plasma is similar to pituitary beta E IR, being mostly nonacetylated and similar in size to beta-lipotropin. These findings are consistent with a pituitary source for the elevated plasma beta E IR found during late pregnancy which may, in turn, be a consequence of elevated plasma concentrations of placentally secreted plasma corticotropin-releasing factor IR present during the third trimester.
...
PMID:Beta-endrophin immunoreactivity during human pregnancy. 146 47

In vivo and in vitro studies were carried out in a 37-year old female with cyclical Cushing's disease. Preoperative studies revealed periodic secretions of urinary corticosteroids occurring with a cyclicity of 2-3 weeks. On transsphenoidal surgery, a microadenoma was visualized in the anteroinferior portion of the anterior pituitary. Gel filtration analyses of the adenoma and surrounding tissues revealed increased concentrations of beta-endorphin and an activated conversion of beta-lipotropin to beta-endorphin in the adenoma compared with the surrounding tissues. These findings were in agreement with the characteristics previously reported for corticotroph adenomas. However, unexpectedly, concentrations of ACTH and beta-lipotropin in the adenoma were only slightly higher than those in the surrounding tissues. Precise mechanisms underlying this unusual finding were elusive, but it may have been due to the periodic nature of her hypercortisolism. In addition, this patient was reproducibly responsive to bromocriptine (2.5 mg, per os) with a reduction of the plasma cortisol level. Although this may suggest an intermediate lobe subtype of Cushing's disease as proposed by Lamberts' group, our case did not have any other characteristic suggestive of this proposed variant. However, it is tempting to speculate that cyclical changes in the central dopaminergic tone may have been at least a partial trigger for the periodic hormonogenesis in this patient.
...
PMID:In vivo and in vitro studies in a patient with cyclical Cushing's disease showing some responsiveness to bromocriptine. 166 81

A fragment of human genomic DNA containing the entire pro-opiomelanocortin (POMC) gene was introduced by transfection into the rat glial cell line C6. Blot analysis using poly(A)-rich RNA from the transformed C6 cells showed several hybridization bands. One band was similar in size (1.2 kb) to the POMC mRNA of human pituitary, while two were larger (2.6 and 2.2 kb) and the fourth smaller (800 bp). S1 nuclease mapping revealed that the POMC transcripts in transformed C6 cells were similar to those in non-pituitary tissues. Immunoreactive ACTH (ir-ACTH) was measurable in both the culture medium and cells. Gel chromatography showed that ir-ACTH in the medium eluted at a position identical to that of so-called big ACTH (approximately 40 kDa) which is found in the plasma of patients with ectopic ACTH syndrome. The human POMC gene could thus be expressed in the non-pituitary rat glial cell line C6, although the transcripts and translation products in C6 cells differ from those in the human pituitary. These results suggest that the transformed C6 cell may be a useful tool for studying the regulation of human POMC gene expression in non-pituitary cells.
...
PMID:Expression of the human pro-opiomelanocortin gene introduced into a rat glial cell line. 216 Aug 27

The distribution of the proopiomelanocortin-derivated amidated joining peptide (JP-N) was examined in the human pituitary gland, adrenal gland, gut and in three bronchial carcinoids. Double immunostaining showed coexistence of immunoreactive JP-N and other proopiomelanocortin derivatives, e.g., ACTH, beta-endorphin, Pro-tau-MSH, in the pituitary gland and adrenal medulla. The JP-N immunoreactive cells in the adrenal medulla were identified as a subpopulation of adrenaline-producing cells by means of an antiserum against phenylethanolamine N-methyltransferase. In the gut immunoreactive JP-N was costored with somatostatin in endocrine cells. Using radioimmunoassay, JP-N was found in higher concentrations than ACTH and alpha-MSH in the gut but not in the adrenal gland. Gel chromatography of gastric antrum and adrenal gland extracts showed three and two dominating components of immunoreactive JP-N, respectively, but under reduced conditions most of the immunoreactive material appeared as of low molecular weight in both extracts. In conclusion, immunoreactive JP-N is a major product from the processing of proopiomelanocortin in human extrapituitary tissues. The molecular forms of immunoreactive JP-N correspond to previous findings in the human pituitary gland.
...
PMID:Amidated joining peptide in the human pituitary, gut, adrenal gland and bronchial carcinoids. Immunocytochemical and immunochemical evidence. 218 29

The aims of the present experiments were: 1) to test whether substances which modulate beta-endorphin-immunoreactive (beta E-ir) release from the pituitary gland might act similarly in hypothalamic tissue; and 2) to further characterize the beta E-ir forms which are released from hypothalamus. To address these questions, hypothalamic tissue was incubated in vitro for 10 min periods in either normal media (basal conditions) or in media containing 55 mM KCl or one of several other test substances (stimulation conditions) and release was estimated by measuring the beta E-ir concentrations in the media. Depolarizing concentrations of K+ increased beta E-ir release 2-3 fold over basal levels and this effect appeared to be Ca2(+)-dependent. Dose-dependent increases in beta E-ir release were elicited by nanonolar to micromolar concentrations of either corticotropin-releasing hormone (CRH), arginine vasopressin (AVP), or 5-hydroxytryptamine (5-HT). Conversely, dopamine (1 microM) inhibited both the basal and K(+)-stimulated release of beta E-ir from hypothalamus. Gel filtration chromatography revealed that beta E1-31 and beta E1-27/beta E1-26 were the primary beta E-ir peptides released under either basal or CRH-stimulated conditions; the relative amounts of the beta E-ir peptides found in the media were nearly identical to those found in the hypothalamus itself. This result indicates that the release of different beta E-ir peptides into the media appears to be proportional to the relative amounts stored in tissue.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:In vitro release of hypothalamic beta-endorphin (beta E) by arginine vasopressin, corticotropin-releasing hormone and 5-hydroxytryptamine: evidence for release of opioid active and inactive beta E forms. 225 Jul 65

Immunoreactive corticotropin-releasing hormone in the amniotic fluid of both human beings and rats was measured by a specific radioimmunoassay. In human subjects the hormone was detectable in all amniotic fluid samples (obtained during the sixteenth and eighteenth weeks of gestation) (2.5 +/- 1.7 fmol/ml, mean +/- SD, n = 17) and the thirty-eighth to fortieth weeks (9.3 +/- 5.4 fmol/ml, n = 24). The levels of concentration of this hormone in this amniotic fluid correlated significantly with the levels in both maternal plasma and placenta for each patient. Gel filtration of amniotic fluid extracts revealed two major peaks of immunoreactive corticotropin-releasing hormone, one at the elution position of the rat hormone and the other at a small-molecular-weight region. Immunoreactive corticotropin-releasing hormone was not detectable in rat amniotic fluid or placenta. We concluded that immunoreactive corticotropin-releasing hormone, which may be derived from the placenta, is present in human amniotic fluid and that its detection in the human placenta but not in rat placentas suggests that the mechanism of corticotropin-releasing hormone gene expression in the placenta is species specific.
...
PMID:Immunoreactive corticotropin-releasing hormone in amniotic fluid. 240 47


1 2 3 4 5 6 7 8 9 10 Next >>