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)

gamma MSH, a putative hormone in the N-terminal region of the ACTH/beta-endorphin (beta-EP) precursor protein, was studied by RIA with an antiserum against gamma 3MSH in ACTH-producing mouse pituitary tumor cells, AtT-20/D16v. Serial dilution of the culture medium or the cell extract gave parallel lines to the standard curve in the RIA for gamma MSH. Rat median eminence extracts enhanced the release of gamma MSH-like immunoreactivity (gamma MSH-LI) concomitant with ACTH-like immunoreactivity (ACTH-LI) and beta-EP-like immunoreactivity (beta-EP-LI). Dexamethasone suppressed the release of gamma MSH-LI as well as ACTH-LI and beta-EP-LI. Gel exclusion chromatography of the culture medium and the cell extract has revealed that gamma MSH-LI consists of two peaks; one eluted near the elution position of beta-lipotropin and the other near the elution position of beta-EP. There was no peak corresponding to the elution position of synthetic gamma 3MSH. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) has demonstrated that gamma MSH-LI migrated at five positions with molecular weights of 31K, 21-23K, 16-17K, 13-14K, and 3.8K, respectively. The 31K gamma MSH coincided with the migration position of 31K ACTH of 31K beta-EP, and 21-23K gamma MSH coincided with the position of 21-23K ACTH on SDS-PAGE. The 16-17K gamma MSH coincided with the mouse 16K fragment (reported by Eipper and Mains) of ACTH-beta-lipotropin precursor protein in the migration in SDS-PAGE and in immunoreactivity to anti-gamma MSH antiserum. [3H]Glucosamine was incorporated into 16K, 13K, and 3.8K gamma MSH. These results suggest that AtT-20/D16v cells produce gamma MSH-LIs with molecular weights of 31K, 21-23K, 16-17K, 13-14K, and 3.8K, and they are secreted concomitantly with ACTH-LI and beta-EP-LI.
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PMID:Characterization of gamma-melanotropin-like immunoreactivity and its secretion in an adrenocorticotropin-producing mouse pituitary tumor cell line. 628 79

Corticotropin releasing factor (CRF) has recently been identified, purified and shown to be a 41-amino acid polypeptide that stimulates secretion of beta-endorphin and ACTH. The metabolic clearance rates (MCR) of I125-CRF and I125-TyroCRF were measured in cynomologus monkeys using the pulse injection and the continuous infusion methods. Hunter-Bolton reagent was used for iodination of CRF and the chloramine-T method for Tyro-CRF. Gel chromatography was used to separate free iodine (and radioiodinated small fragments) from iodinated CRF in plasma samples. Disappearance of I125-CRF or I125-Tyro-CRF could be modeled with two components (bi-exponential). Plasma half-life of I125-CRF was 17.1 +/- 2.44 min (mean +/- SE, n=4) for the fast component and 198 +/- 5.3 min for the slow component. The MCR of I125-CRF using the pulse injection technique was 0.44 +/- 0.06 L/Kg/d, n=4 and the volume of distribution 213.5 +/- 12 ml, n=4, roughly equal to the plasma volume. Continuous infusion of I125-CRF and of I125-Tyro-CRF gave MCR's ranging between 2.23 -= 5.08 L/Kg/d, n=4. I125-ACTH MCR, measured for comparison using the same technique, was 5-10 fold higher. Thus, the plasma half-life of CRF is longer than for all other known hypothalamic peptides and its metabolic clearance rate relatively low and considerably less all other known hypothalamic peptides and its metabolic clearance rate relatively low and considerably less than that of ACTH. Strong binding of CRF to plasma proteins may be responsible for the small volume of distribution and lower MCR values for the pulse injection method.
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PMID:Metabolic clearance rate and plasma half-life of radioiodinated corticotropin releasing factor in a primate. 628 52

In response to mild stress the levels of immunoreactive beta-endorphin in rat anterior pituitary, hypothalamus and pineal fell within 10 minutes from 210 to 129 pmol/lobe, 1.47 to 0.89 pmol/mg protein and 2.53 to 0.41 pmol/gland, respectively. No alterations were found to take place in beta-endorphin levels in posterior pituitary or plasma. Dexamethasone pretreatment given 18 h prior to stress resulted in significantly greater reduction of beta-endorphin levels in hypothalamus and pineal than stress alone--hypothalamic levels fell to 0.73 pmol/mg protein and pineal to 0.07 pmol/gland. Plasma beta-endorphin levels in dexamethasone pretreated stressed rats were significantly lower than in intact rats (42 fmol/ml vs. 98 fmol/ml). The almost complete disappearance of beta-endorphin from the pineal in response to stress and dexamethasone suggests that pineal does not itself synthesize the hormone but only utilizes and/or stores it. Gel filtration analysis of the beta-endorphin immunoreactivity in tissue extracts and plasma showed that anterior pituitary and plasma contain three immunoreactive components, eluting like beta-endorphin, beta-lipotropin and proopiocortin, whereas only beta-endorphin-like material was detected in posterior pituitary, hypothalamus and pineal.
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PMID:Effect of stress and dexamethasone on immunoreactive beta-endorphin levels in rat hypothalamus and pineal. 629 33

Rat brain membranes (RBM) bind beta-endorphin with high affinity and specificity. We report herein the identification of a high molecular weight beta-endorphin complex (receptor) in extracts of RBM preincubated with tritiated beta-endorphin, by using the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS). Upon isoelectric focusing, this complex gives a single peak with an isoelectric point (+/- SEM) of 4.50 +/- 0.06. Sucrose density gradient experiments in H2O and 2H2O yield effective partial specific volume (v = 0.814 cm3/g and sedimentation constant s20,w = 15.6 S. Gel filtration yields an estimate of the hydrodynamic radius of 73 A. The corresponding frictional ratio of 1.12 is consistent with an elliptical spheroid with an axial ratio of 3.1-3.2. The molecular mass of the complex is estimated to be 690,000 daltons. The v of the complex is greater than that of CHAPS or most globular proteins.
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PMID:Characterization of beta-endorphin binding protein (receptor) from rat brain membranes. 629 4

Female Wistar rats of different ages (1-45 days) were used. Extracts were made of the mediobasal hypothalamus (MBH) and beta-endorphin immunoreactivity (beta-ENDi) was quantitated by radioimmunoassay. Low but significant amounts of beta-ENDi (6.5 ng/MBH) were present on the first postnatal day. Hypothalamic beta-ENDi content did not change during the first week but decreased during the second week to a minimum (4.5 ng/MBH) on day 14. Thereafter, beta-ENDi increased rapidly to 13 ng/MBH on day 28 and remained at this level. Gel filtration showed that beta-ENDi substances with chromatographic characteristics identical to those of beta-END and beta-LPH were present in MBHs of 14-, 20- and 45-day-old rats. A beta-ENDi substance, possibly representing beta-END1-27, was nearly absent on day 14, but represented a major component of the MBH of the 45-day-old rat. In vitro incubation of MBH resulted in spontaneous release of beta-ENDi. Depolarization of neuronal membranes by incubation in medium containing 45 mMK+ stimulated beta-ENDi release. Both the spontaneous and K+-stimulated release of beta-ENDi were low on day 10 but reached postpubertal levels on day 20. These observations lead us to propose that the beta-ENDi-containing neurons in the hypothalamus of developing female rats rapidly mature between 14 and 20 days after birth. This may be causally related to the rapid decrease in circulating FSH levels that occurs during this period.
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PMID:Immunoreactive beta-endorphin in the hypothalamus of female rats: changes in content and release during prepubertal development. 629 64

Levels of immunoreactive (IR) human NH2 terminal (HNT) of pro-opiomelanocortin were determined serially in 80 patients with various pulmonary carcinomas, 20 patients with various pulmonary diseases without proven carcinoma, and 32 normal control subjects. Sixty +/- 14% (S.E.) (95% confidence interval) of the patients with proven pulmonary carcinoma had elevated values of IR HNT in plasma (greater than 100 pg/ml); the highest frequency of elevated IR HNT was found in patients with small-cell carcinoma [74 +/- 14.5% (95% confidence interval)]. In eight patients with pulmonary tumor who underwent surgical thoracic exploration, the plasma level of IR HNT in the pulmonary vein was 50.6 +/- 21.4% (95% confidence interval; N = 8) higher than that in the pulmonary artery. The levels of IR HNT correlated well with those of plasma adrenocorticotropic hormone (IR ACTH) (r = 0.988; p less than 0.001); however, the level of IR HNT was 3- to 4-fold higher than that of IR ACTH. Gel permeation chromatography of plasma of patients with pulmonary carcinoma revealed a major peak of IR HNT coinciding with the elution volumes of authentic HNT (Mr 12,000) and a minor peak of IR HNT near the void volumes. These results suggest that HNT originating from pulmonary carcinoma is chemically and immunologically similar to that from human pituitary gland and that measurement of plasma IR HNT may indicate the state of secretion and/or metabolism of peptides related to the expression of the pro-opiomelanocortin gene in human pulmonary carcinoma. The HNT immunoassay is a simple procedure which, contrary to that of ACTH, does not require plasma extraction prior to the assay. This suggests the possibility that measurement of IR HNT alone and in conjunction with other biochemical markers could be a useful parameter for diagnosis and follow-up of patients with pulmonary carcinoma.
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PMID:Human NH2 terminal of pro-opiomelanocortin as a potential marker for pulmonary carcinoma. 630 75

5 micrograms of human beta-endorphin were labelled with 2 mCi 125I by the chloramine T technique. After two gel filtrations on Sephadex G-15 and on Sephadex G-50 in phosphate buffer with EDTA, Trasylol and mercapto-ethanol, a pure tracer was obtained with a specific activity about 150 microCi/ug. Kept at + 4 degrees C, the tracer remained utilizable for 30 days without loss of immunoreactivity. The labelling with lactoperoxydase and the use of another gel filtration method (filtration on Aca 202) gave a 125I beta-END tracer with the same immunoreactivity. The binding of this tracer to the antibody of an anti-beta-END antiserum diluted at 1/8000 was 32% with a non specific binding of 2%. 5 micrograms of human beta-lipotropin were labelled with 0.5 mCi 125I by the lactoperoxydase method. After two gel filtrations on Sephadex G-25 and on Sephadex G-75 in phosphate buffer with EDTA, Trasylol and mercapto-ethanol, a pure tracer with a specific activity of 140 microCi/micrograms was obtained. It remained utilizable for 30 days when kept at + 4 degrees C. Gel filtration on Aca 202 did not give good purification, while gel filtration on Aca 54 was good but slower than on Sephadex G-75. The binding to antibody in absence of unlabelled beta-LPH was 32% for an anti-beta-LPH antiserum diluted at 1/4000. The non specific binding was 2.5%.
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PMID:[Labeling of beta-endorphin and beta-lipotropin with iodine 125]. 630 39

A commercially available preparation of corticotropin was found to have potent cytotoxic activity for several established cell lines. Neither synthetic corticotropin nor alpha melanocyte stimulating hormone demonstrated this cytotoxic activity. Gel filtration allowed separation of a 2100 dalton cytotoxic peptide from the actual corticotropin present in the commercially prepared material. The structural relatedness of the cytotoxic peptide to corticotropin was demonstrated by neutralization with antisera to alpha melanocyte stimulating hormone. These studies indicate the existence of a newly identified ACTH related peptide with cytotoxic activity.
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PMID:A corticotropin (ACTH) related peptide with cytotoxic activity. 631 Dec 8

Cerebrospinal fluid (CSF) samples were taken from rats implanted with chronic cisternal cannulae and assayed for methionine-enkephalin, beta-endorphin and corticotropin (ACTH). Immobilization stress had little apparent effect on immunoreactive levels of the peptides in the CSF. Gel chromatographic analysis of the beta-endorphin- and ACTH-immunoreactive profiles in rat CSF revealed several peaks. beta-Endorphin-immunoreactive peaks were present at the expected positions of pro-opiocortin, beta-lipotropin and beta-endorphin. ACTH-immunoreactive peaks eluted at positions corresponding to pro-opiocortin, the 20-23K ACTH biosynthetic intermediate, 14K ACTH, and 4.5K ACTH. These results suggest that rat CSF contains peptides of the pro-opiocortin family similar to those previously described in rat pituitary.
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PMID:Endorphin-related peptides in rat cerebrospinal fluid. 631 85

The regional distribution of pro-opiocortin-derived peptides and methionine enkephalin was investigated in human brain post-mortem. Sequence-directed radioimmunoassays for beta-endorphin, gamma-lipotropin, adrenocorticotrophin, corticotrophin-like intermediate lobe peptide (ACTH18-39, CLIP) alpha-MSH and methionine enkephalin were used and 40 different human brain areas were assayed. The regional distribution of all the pro-opiomelanocortin-derived immunoreactivities were correlated with highest amounts of beta-endorphin, gamma-lipotropin and ACTH in the hypothalamus, amygdala, periventricular grey, substantia nigra and superior colliculus. The distribution of beta-endorphin, gamma-lipotropin and ACTH did not parallel the distribution of methionine-enkephalin immunoreactivity which was present in the globus pallidus, nucleus accumbens and substantia nigra. Gel exclusion chromatography (G-50) showed that pro-opiocortin-related peptides in the human hypothalamus and periventricular grey separated in positions consistent with the major immunoreactive forms being beta-endorphin, gamma-lipotropin, ACTH and CLIP.
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PMID:Regional distribution of pro-opiomelanocortin-derived peptides in the human brain. 632 29


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