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)

Iodinated beta H-[2-D-alanine]endorphin exhibits specific binding to cultured human lymphocytes. The binding is inhibited by low concentrations of beta-endorphin and its D-alanine derivative, but is not affected by opiate agonists and antagonists, or by enkephalin analogs, beta-lipotropin, adrenocorticotrophic hormone, or alpha-melanocyte-stimulating hormone; this suggests the existence of a specific, non-opiate binding site (receptor) for beta-endorphin. The carboxy-terminal region of beta-endorphin is essential for this binding activity, since alpha-endorphin is not active. beta-Endorphin may be a circulating hormone with peripheral physiological effects that are not primarily mediated through interactions with opiate or enkephalin receptors.
Science 1979 Sep 07
PMID:Specific nonopiate receptors for beta-endorphin. 22 57

This review presents an analysis and interpretation of the published experimental data that form the basis for laboratory tests commonly used for screening, definitive diagnosis, and differential diagnosis in Cushing's syndrome. The single-dose overnight dexamethasone suppression test is excellent for screening outpatients since this test has a very low incidence of false-negative results (1.9% of 154 patients with Cushing's syndrome). The definitive diagnosis of Cushing's syndrome is best established by combining basal state measurements of the daily urine-free cortisol excretion and late evening plasma cortisol levels with the 2-mg low-dose dexamethasone suppression test. The etiology of Cushing's syndrome is best determined by combining measurements of basal state plasma adrenocorticotropin (ACTH) levels with the 8-mg high-dose dexamethasone suppression test. Under certain conditions, the basal state daily urine excretion of 17-hydroxycorticosteroids and 17-ketogenic steroids, the insulin tolerance test, and the metyrapone test may be useful in the definitive or differential diagnosis of Cushing's syndrome.
Metabolism 1979 Sep
PMID:Cushing's syndrome: a review of diagnostic tests. 22 38

The high molecular weight forms of adrenocorticotropic hormone (ACTH) produced by mouse pituitary tumor cells (AtT-20/D-16v) were separated from each other by gel filtration; their ability to stimulate steroidogenesis by isolated rat adrenal cortical cells was studied. Pools of pro-ACTH/endorphin. ACTH biosynthetic intermediate, and glycosylated ACTH(1--39) were obtained; on the basis of NaDodSO4-polyacrylamide gel electrophoresis, over 97% of the immunoactive ACTH was found to have the expected molecular weight. Suspension of isolated rat adrenal cortical cells were incubated overnight in tissue culture medium and used in a 2-h steroid production assay. Synthetic human ACTH(1--39) [hACTH(1--39)] was used as a bioassay and immunoassay standard; 60 pM hACTH(1--39) stimulated half-maximal production of fluoregenic steroid. The amount of pro-ACTH/endorphin, ACTH biosynthetic intermediate, or glycosylated (ACTH(1--39) added was estimated with an ACTH(17--24) immunoassay. All three high molecular weight forms of ACTH are capable of stimulating the same maximal level of steroidogenesis as hACTH(1--39). Glycosylated ACTH(1--39) is equipotent with hACTH(1--39); ACTH biosynthetic intermediate and pro-ACTH/endorphin are, respectively, 100- and 300-fold less potent than hACTH(1--39). Steroid production in response to all four forms of ACTH is linear in time. All of the different forms of ACTH stimulate the synthesis of corticosterone and related steroids; no significant production of cortisol or aldosterone was observed. beta-Lipotropin (beta LPH) and 16K fragment, which comprise the non-ACTH regions of pro-ACTH/endorphin and are secreted by the pituitary tumor cells, did not stimulate or interfere with steroidogenesis. Brief incubations of pro-ACTH/endorphin and ACTH biosynthetic intermediate with trypsin generated lower molecular weight forms of ACTH and increased biological activity 50-fold; thus, the decreased steroidogenic potency of these forms of ACTH is thought to be due to structural constraints on the ACTH(1--39)-like sequence in these larger precursor molecules
Biochemistry 1979 Sep 18
PMID:Steroidogenic activity of high molecular weight forms of corticotropin. 22 22

Substance P stimulation of salivation in rats has been studied as has its in vitro enhancement of amylase release by isolated parotid cells. The extent of the stimulation on amylase release by isolated parotid cells was dependent upon the concentration of substance P, with the minimum effective concentration being 1 nM. The substance P effect was detectable within 1 min after incubation and lasted for at least 50 min. Substance P stimulation was demonstrable at 25--37 degrees C but not at 0 degrees C. Adrenocorticotropic hormone (ACTH), thyrotropin-releasing hormone (TRH), vasopressin and neurotensin had no effect on amylase release. These results suggest that substance P may act directly on the parotid cells. Examination of the salivary-stimulating activity of fragments of substance P showed that the C-terminal octapeptide and (pyroglutamyl)hexapeptide were active, although less potent than substance P, whereas its free acid, C-terminal tetra- and tri-peptides were inactive. Vasopressin, angiotensin II and neurotensin could inhibit substance P induced salivation, whereas TRH, ACTH and somatostatin had no effect. Amylase activity per unit volume of saliva was not changed by the injection of vasopressin, angiotensin II or neurotensin. These vasoactive peptides did not affect substance P stimulation of amylase release by isolated parotid cells. The results indicate that vasopressin, angiotensin II and neurotensin inhibit the action of substance P on salivation at sites other than the parotid cells.
Mol Cell Endocrinol 1979 Sep
PMID:Substance P stimulation of amylase release by isolated parotid cells and inhibition of substance P induction of salivation by vasoactive peptides. 22 41

Ovine corticotropin (alpha s-ACTH) was enzymatically methylated with purified calf brain protein methylase II (protein O-methyltransferase; S-adenosyl-L-methionine: protein-carboxyl O-methyltransferase, EC 2.1.1.24) and S-adenosyl-L-[methyl-14C]methionine. After incubation for 60 min at 37 degrees C, 30 mol % of the hormone was methylated on the basis of the [14C]methyl incorporation. In order to assess the location of methylation, the modified peptide was digested with pepsin. Analytical results derived from studies on the peptic digest led to the suggestion that the alpha s-ACTH-(6--28) peptide fragment was esterified. Because there is only one available methylation site at Glu-28, these results indicate that Glu-28 of alpha s-ACTH was specifically methyl esterified to yield [Glu(OMe)28]-alpha s-ACTH.
Proc Natl Acad Sci U S A 1979 Sep
PMID:Enzymatic methyl esterification of specific glutamyl residue in corticotropin. 22 92

Studies on the biosynthesis of beta-LPH on the one hand, and of ACTH on the other, have produced a new concept, that of a single precursor form which contains three active molecules. Thus, it is proper to name such a precursor 'pro-opio-melanocortin.' The concept that beta-LPH was a precursor molecule was first put forward in 1967 and was based on both structural forms and biological activities. The discovery that morphine-like substances are part of the C-terminal fragment of beta-LPH brought an additional important biological side product. That, together with the recent demonstration of ACTH as part of a still larger precursor, constitutes an exciting model for the study of peptide hormone biosynthesis. We have shown unambiguously that beta-endorphin is the result of a maturation process from the large precursor, while beta-LPH is an important and transient intermediary. Since it is also present in the brain, our recent results using pars intermedia cells can be applied to study the fabrication and degradation of these molecules in the brain. We expect to see it established that all other neuropeptides are also biosynthesized as larger precursor molecules whose structure at the site of cleavage could well be constituted of two basic amino acids like in the pro-opio-melanocortin.
Can J Biochem 1979 Sep
PMID:From beta-lipotropin to beta-endorphin and 'pro-opio-melanocortin'. 22 24

The mechanism of corticotropin stimulation of the synthesis of a specific rat adrenal cytosolic protein was investigated. This protein (protein E) has a mol.wt. of approx. 30000. It is detected by polyacrylamide-gel electrophoresis of cytosol prepared from adrenal slices from rats treated with corticotropin in vivo and control rats, the slices being incubated with [(3)H]- and [(14)C]-leucine respectively. In rats 1-15 days after hypophysectomy, corticotropin, like dibutyryl cyclic AMP, induces an increase in protein E similar to that induced in control rats, even though both compounds no longer stimulate total protein synthesis. Corticotropin stimulation of protein E synthesis is mediated by cyclic AMP but not by corticosterone, since aminoglutethimide, a steroidogenic inhibitor, does not affect corticotropin stimulation, and dexamethasone alone has no effect. Actinomycin D, when injected in vivo 1h before or after corticotropin injection, prevents the effect of corticotropin on protein E synthesis, which is interpreted as evidence that mRNA synthesis is necessary for the stimulation of protein E synthesis. When injected more than 2h after corticotropin, actinomycin D does not prevent corticotropin stimulation of protein E synthesis, but completely blocks corticotropin stimulation of total protein synthesis. This is interpreted as meaning that, after stimulation of mRNA coding for protein E, corticotropin has no effect on the synthesis of protein E. On the other hand, corticotropin stimulation of protein E synthesis persists after hypophysectomy even though it no longer stimulates total protein synthesis. These data suggest that the factor(s) involved in the synthesis of protein E are more stable than those involved in total protein synthesis.
Biochem J 1979 Sep 15
PMID:Corticotropin regulation of the synthesis of a specific rat adrenal cytosolic protein. Effects of hypophysectomy and actinomycin D. 22 25

The time course of plasma bioactive adrenocorticotropin (ACTH) concentrations measured following two rapid injections of the hormone at doses of 7.5 and 22.5 mU/100 g, iv, and one infusion over a period of 80 min at a rate of 1.3 mU/min per 100 g, to male Sprague-Dawley rats whose endogenous release of ACTH had been blocked, leads to the conclusion that the hormone is distributed in two compartments. Indeed, the rapid fall of plasma ACTH concentrations in the early minutes following either the injections or the stop of the infusion is followed by a much slower phase. There is no significant difference between the measurements and the two-compartment model outputs. The model represents, on the average, the mean values of the measurements plus or minus 1 standard error for the single injections and plus or minus 1.2 standard error for the infusion.
Can J Physiol Pharmacol 1979 Sep
PMID:Distribution and metabolism of adrenocorticotropin in the rat. 22 48

Neurons simultaneously immunoreactive with anti-beta-endorphin and anti-(17-39) corticotropin (anti(17-39) ACTH) have been detected in the arcuate and ventromedial nuclei of the hypothalamus of colchicine-treated rats. These neurons are different from those fluorescent with the Falck and Hillarp technique. These results show that in the arcuate nucleus, immunoreactive ACTH and beta-endorphine are stored in the same neurons which are different from dopamine-containing neurons.
Neurosci Lett 1979 Sep
PMID:Comparative study of the neuronal populations containing beta-endorphin, corticotropin and dopamine in the arcuate nucleus of the rat hypothalamus. 23 Dec 30

Melatonin levels exhibited a day-night rhythm with highest levels at night. Nocturnal plasma melatonin concentrations were unrelated to sleep stages, whereas secretion of GH was temporally related to slow wave sleep. Levels of corticotropin rose in the later sleep cycles. We found no relationship between endogenous nocturnal melatonin and adenohypophyseal hormone levels. The results indicate that in young men nocturnal levels of melatonin are controlled separately from those of LH, PRL, corticotropin, and GH.
J Clin Endocrinol Metab 1978 Sep
PMID:Overnight plasma profiles of melatonin and certain adenohypophyseal hormones in men. 23 75


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