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 human and the bovine corticotropin (ACTH)-beta-lipotropin (LPH) precursor gene have been isolated and characterized. Both genes consist of three exons which are divided by two large introns at exactly the same positions. One of the introns is inserted within the segment transcribed into the 5'-untranslated region of the mRNA, and the other interrupts the protein-coding sequence near the signal peptide region. The largest exon encodes most of the protein sequence which includes the three repeated melanotropin (MSH) peptides and other biologically active peptides such as ACTH and beta-endorphin. Thus, there is no apparent correspondence between the repetitive structure of the precursor protein and the structural organization of its gene. Comparison of the nucleotide sequences of the human and the bovine gene reveals that three regions are highly conserved, i.e., the region extending from the signal peptide to gamma-MSH, the ACTH region and the beta-MSH/beta-endorphin region. This suggests that the peptide(s) in the amino-terminal region, including gamma-MSH, may be of physiological importance, as is the case for ACTH and beta-endorphin. The different biologically active component peptides of the ACTH-beta-LPH precursor, encoded by a single gene, seem to be involved in the defense mechanism of the living organism by acting coordinately in the central nervous system as well as in peripheral tissues. The identification of the mRNA encoding the ACTH-beta-LPH precursor in a human ectopic ACTH-producing tumor is also reported.
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PMID:Structural organization of the corticotropin-beta-lipotropin precursor gene. 630 21

In order to investigate the biosynthesis of alpha MSH and beta-endorphin in a non-mammalian vertebrate, individual lizard intermediate pituitaries were incubated in complete medium containing a radioactive amino acid, using either a steady label or a pulse/chase protocol. Following incubation, acid extracts of the tissue were immunoprecipitated with either an NH2-terminal ACTH antiserum or a beta-endorphin antiserum and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. After a 24 hr steady label in medium containing [3H]tyrosine, multiple molecular weight forms of beta-endorphin-related and NH2-terminal ACTH-related radioactivity were detected. The major peak of beta-endorphin-related radioactivity co-migrated with synthetic beta-endorphin(1-31); minor peaks of beta LPH-sized material and precursor-sized material were also detected. The major peak of NH2-terminal ACTH-related material co-migrated with synthetic alpha MSH; in addition, smaller amounts of material designated ACTH biosynthetic intermediate 1, ACTH biosynthetic intermediate 2, and precursor-sized material were detected. Sequential immunoprecipitation experiments revealed that the precursor-sized material had antigenic determinants for both alpha MSH and beta-endorphin. Pulse/chase experiments established that this material is the common precursor for alpha MSH and beta-endorphin. Based on gel filtration chromatography in 6 M guanidine HCl, the molecular weights of these various peptides are: common precursor, 23,300 daltons; ACTH biosynthetic intermediate 1, 12,200 daltons; ACTH biosynthetic intermediate 2, 4,200 daltons; alpha MSH, 1,500 daltons; beta LPH, 8000 daltons; beta-endorphin, 3,400 daltons. None of the peptides precipitated with either antiserum incorporated [3H]glucosamine; thus glycosylation does not appear to be involved in this biosynthetic pathway in the lizard. The results of the kinetic experiments and molecular weight determinations indicate that the major biosynthetic pathway involves the following events: common precursor is first cleaved to yield ACTH biosynthetic intermediate 1 plus beta LPH; subsequently, beta LPH is cleaved to produce beta-endorphin; ACTH biosynthetic intermediate 1 is cleaved to produce ACTH biosynthetic intermediate 2 which is subsequently cleaved to produce alpha MSH. The pulse/chase experiments indicate minor pathways exist for cleaving beta-endorphin directly from the common precursor or via a high molecular weight form intermediate in size between the common precursor and beta LPH.
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PMID:Evidence for a common precursor for alpha MSH and beta-endorphin in the intermediate lobe of the pituitary of the reptile Anolis carolinensis. 630 Aug 8

The major objective of this study was to investigate the analogy existing between the typical circadian periodicity of ACTH and that recently described of beta-lipotropin (beta-LPH) and beta-endorphin (beta-EP) plasma levels. The determination of their concentrations, plus cortisol, has been performed on the same plasma samples of 6 healthy volunteers. All hormones were measured by radioimmunoassay. Those of beta-LPH and beta-EP were preceded by a purification of plasma through silicic acid extraction and Sephadex G-75 gel filtration. The highest values (mean +/- SEM) were found in the morning (ACTH: 10.3 +/- 0.9; beta-LPH; 6.3 +/- 0.7; beta-EP: 6.5 +/- 0.5 fmol/ml; cortisol: 378 +/- 30 pmol/ml) and the lowest values in the evening (ACTH: 6:1 +/- 0.7; beta-LPH: 3.3 +/- 0.4; beta-EP: 3.7 +/- 0.6 fmol/ml; cortisol: 130 +/- 23 pmol/ml). Statistical analysis using the Fourier method led to the evidence of a concomitant circadian secretory pattern of the three proopiocortin-related peptides. These results strongly suggest that the phasic secretion of ACTH, beta-LPH and beta-EP underlies a common central control.
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PMID:Simultaneous circadian variations of plasma ACTH, beta-lipotropin, beta-endorphin and cortisol. 630 34

The plasma patterns of ACTH, beta-lipotropin (beta LPH) and beta-endorphin (beta EP), in addition to those of cortisol and dehydroepiandrosterone sulfate (DHAS), were studied in 139 prepubertal children (subdivided into different age groups) and 38 adolescents (subdivided according to Tanner's pubertal stages) aged 10-16 yr. The adult control group was composed of 23 females and 12 males aged 17-40 yr. No sex differences were found in ACTH, beta LPH, beta EP, and cortisol plasma levels. ACTH plasma levels were slightly lower in the 1- to 3-yr-old groups than in males at 4-5 yr and females at 8-9 yr. No further significant differences were observed in any of the age or pubertal groups, the concentrations being constantly in the adult range. beta LPH and beta EP plasma levels were lowest at 1-3 yr in both males (beta LPH: 2.1 +/- 0.25, beta EP: 1.85 +/- 0.59 fmol/ml, mean +/- SE) and females (beta LPH: 2.8 +/- 0.31; beta EP: 2.41 +/- 0.41 fmol/ml); plasma levels of both hormones increased progressively in both sexes until Puberty 1 stage of sexual maturation, at which time levels were 7.3 +/- 0.78 and 8.69 +/- 1.0 fmol/ml in males and 7.1 +/- 0.34 and 6.76 +/- 0.13 fmol/ml in females; these levels are similar to adult values. A highly significant linear correlation was found between both beta LPH and beta EP concentrations and the age of the subjects; this was not true for ACTH plasma levels. Cortisol plasma levels were similar in all groups. DHAS plasma levels increased progressively from 1-3 yr to the end of sexual maturation when adult values were reached. During prepuberty, DHAS levels were significantly correlated with both beta LPH and beta EP, but not ACTH. These data indicate that plasma beta LPH and beta EP concentrations, in contrast to ACTH levels, increase progressively throughout prepuberty and suggest that the processing of the parent proopiocortin molecule or secretion of the processed peptides from the anterior pituitary (or other sources) may change from early infancy to adulthood. Furthermore, the correlation between both beta LPH and beta EP with DHAS plasma levels in prepuberty suggests a role of proopiocortin-related peptides in adrenarche.
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PMID:Proopiocortin-related peptide plasma levels throughout prepuberty and puberty. 630 36

Plasma levels of two endogenous opioid peptides, beta-endorphin and met-enkephalin, as well as immunoreactive N-terminal beta-lipotrophin (N-LPH) were studied in normal pregnant women from 8 to 41 weeks gestation. A total of 116 samples were assayed for beta-endorphin-like immunoreactivity (C-LPH), 103 for N-LPH and 75 for met-enkephalin. Plasma beta-endorphin-like immunoreactivity and N-LPH levels rose progressively throughout gestation and reached a maximum at term. Plasma met-enkephalin immunoreactivity did not significantly change throughout pregnancy. These results reflect an increasing and consistent adrenocorticotrophin (ACTH)/beta-LPH and beta-endorphin secretion throughout pregnancy, while the unchanged met-enkephalin levels are compatible with its known derivation from a separate precursor system.
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PMID:Endogenous opioid peptides in pregnancy. 630 94

Basal and stimulated secretion of N-terminal pro-opiocortin (Pro-gamma-MSH), ACTH and LPH from seven pituitary and three ectopic ACTH secreting tumours have been studied in vitro using a perfused isolated cell system. The peptides were shown to be released concomitantly and in equimolar amounts. The pituitary tumours responded to stimulation with rat stalk median eminence extracts (SME) and synthetic AVP. However, peptide release from the ectopic tumours, although pulsatile, remained autonomous. Prior to surgery, gel-chromatographic profiles of plasma immunoreactive ACTH showed only one peak, which eluted in the position of 1-39 ACTH, in patients with the pituitary tumours, but there was a second peak of large molecular weight ACTH present in the plasma from those with the ectopic ACTH syndrome. This second form of ACTH could not be detected in any of the tumour cell column effluents. An eighth pituitary tumour was atypical, in its unusually large size, clinically aggressive nature and spectrum of peptide release. Although peptide release in response to stimulation with SME was similar to that observed with the other pituitary tumours, the chromatography of the plasma ACTH resembled the ectopic plasma pattern, showing two peaks of immunoreactivity.
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PMID:Pro-opiocortin related peptides in human pituitary and ectopic ACTH secreting tumours. 630 38

Plasma immunoreactive-(IR) beta-endorphin (beta-EP) and beta-lipotrophin (beta-LPH) levels were measured in 15 adult uraemic patients on chronic haemodialysis. The presence of immunoreactivity eluting in the position of beta-EP was demonstrated following submission of pooled extracts of uraemic plasma to gel permeation chromatography on Sephadex G-50. To separate beta-EP from beta-LPH, pre-dialysis plasma extracts from six individual patients, and three pools of three patients each, were submitted to sequential immune-affinity chromatography and levels were measured by radioimmunoassay. In all cases, plasma IR beta-EP concentrations were markedly increased compared with normal subjects (m +/- SEM fmol/ml; 64.4 +/- 13.7 vs. 2.3 +/- 0.2). IR beta-LPH concentrations were also increased (m +/- SEM fmol/ml; 55.7 +/- 13.2 vs. normal 6.1 +/- 0.8). In addition, post-dialysis concentrations of plasma IR beta-EP and beta-LPH were lower than pre-dialysis levels (n = 4).
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PMID:Plasma immunoreactive beta-endorphin is elevated in uraemia. 630 52

The 41-residue ovine corticotropin releasing factor (CRF) was administered iv and intracerebroventricularly (icv) to merino sheep. A significant rise in plasma ACTH, beta-lipotropin (beta LPH) and cortisol was demonstrated after the administration of 200 micrograms, iv. A highly significant correlation between the increments in plasma ACTH and beta LPH was observed. The plasma ACTH rise was evident within 5 min and was abolished by the prior administration of 0.4-4.0 mg dexamethasone. No significant rise in plasma GH, LH, PRL, insulin, glucagon, pancreatic polypeptide, met-enkephalin, angiotensin II, aldosterone, or vasopressin could be demonstrated. Although smaller doses of CRF (50 ng to 5 micrograms) were effective when given icv, the ACTH response was more delayed. It is concluded that CRF stimulates a rapid increase in the secretion of ACTH and beta LPH in sheep. Suppression of this response by dexamethasone indicates that glucocorticoids are capable of acting on the pituitary to inhibit the ACTH response to CRF. The delayed response when CRF is given icv may be due to diffusion. The action of CRF appears to be relatively specific, in that the plasma concentrations of the other pancreatic, pituitary, and adrenal hormones measured were not affected.
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PMID:The hormonal actions of corticotropin-releasing factor in sheep: effect of intravenous and intracerebroventricular injection. 630 69

Extracts of neurointermediate lobe (NIL) and anterior lobe (AL) of the rat pituitary, and material released from perfused rat pars distalis (PD) and pars intermedia (PI) cells were gel chromatographed and monitored using three antisera, each recognizing different regions of the non-corticotropin (ACTH)-lipotropin (LPH) portion of pro-opiocortin (POC). Two peaks (termed N-POC I) which emerged close to the elution position of rat beta-LPH were detected. The first peak was reduced significantly in the PI. Two smaller N-POC fragments which eluted near beta-endorphin were detected only in extracts and secretions of intermediate lobe tissue. One peak cross-reacted in the gamma 3-melanotropin (MSH) assay (N-POC III) whereas the other peak possessed amino (N)-terminal N-POC immunoreactivity (N-POC II). The results demonstrated differences in the distribution and nature of N-POC peptides released and extracted from the PD and PI of the rat pituitary, and suggest that the enzymic processing of N-POC is different in the two pituitary lobes.
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PMID:An investigation of N-terminal pro-opiocortin peptides in the rat pituitary. 631 93

Plasma beta-LPH, beta-EP and gamma-LPH concentrations were measured by radioimmunoassay in 10 pregnant women from 12 weeks gestation until term and in nine women in the early follicular phase of the cycle. There was a progressive and significant rise in the concentration of all three peptides throughout pregnancy and by 32 weeks the concentrations of beta-LPH and beta-EP were greater than the corresponding concentrations in the follicular phase: gamma-LPH was greater than in the follicular phase by the end of pregnancy in those women who were delivered after 40 weeks. The ratio of beta-LPH to gamma-LPH did not change significantly throughout pregnancy, but there was a progressive fall in the beta-LPH/beta-EP ratio. The possible presence of a 'big LPH' to explain this finding is discussed.
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PMID:Maternal plasma concentrations of beta-lipotrophin, beta-endorphin and gamma-lipotrophin throughout pregnancy. 631 6


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