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)

Crude membranes (20,000 times g pellet) prepared from human, rat, and ovine adrenals bind 125-I-corticotropin-(1-24)-tetracosapeptide (125-I-ACTH-1-24) and degrade unbound hormone. The degradation is dependent on temperature and the concentration of membrane proteins. The degradation of 125-I-[9-tryptophan(o-nitrophenylsulfenyl)]-corticotropin-(1-24)-tetracosapeptide (125-I-NPS-ACTH-1-24) is similar to 125-I-ACTH-1-24, but that of 125-I-corticotropin-(11-24)-tetradecapeptide (125-I-ACTH-1-24 is inhibited by ACTH-1-24 and corticotropin-(1-10)-decapeptide (ACTH-1-10), but ACTH-11-24 at the same molar concentration has no effect. On the other hand, the degradation of 125-I-ACTH-11-24 is protected by ACTH-11-24 and ACTH-1-24, but not by ACTH-1-10. This suggests two systems of degradation, one will have the NH-2-terminal sequence of ACTH-1-24 as substrate, and the other the 11-24 COOH-terminal sequence. The main label product from the degradation of the 125-I-ACTH-1-24 and 125-I-ACTH-11-24 behaves as [125-I]monoiodotyrosine on Sephadex G-50 and paper chromatography. The independence of ACTH binding to its receptor and degradation is demonstrated by the following facts. (a) Calcium and pancreatic trypsin inhibitor completely inhibit the binding at concentrations when the degradation is not altered; (b) the sequences of peptides of ACTH which inhibit the binding and degradation of 125-I-ACTH-1-24 are different.
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PMID:Interactions of adrenocorticotropic hormone with its adrenal receptors. Degradation of ACTH-1-24 and ACTH-11-24. 16 55

We have compared the capacity to secrete ACTH in response to stress or adrenalectomy in control rats and in those with total hypophysectomy (H), adenohypophysectomy (AH) with preservation of the intermediate and the neural lobes, neurohypophysectomy (NH) with removal of the pars nervosa and all or part of the pars intermedia with preservation of the adenohypophysis, or incomplete adenohypophysectomy (IAH) in which a portion of the adenohypophysis and all of the pars intermedia and pars nervosa were left intact. Plasma ACTH measured with an N-terminal antibody that reacts on an equimolar basis with ACTH and alpha-MSH but not with other known pituitary hormones was elevated after ether or tourniquet stress in all except the H group. Three weeks after adrenalectomy there was an elevated basal plasma ACTH and an augmented ACTH response to stress in intact and IAH but not in AH rats. When a more specific alpha11-24 ACTH antibody was used there was a high plasma ACTH after ether stress in the IAH, NH, and intact groups but not in the AH or H groups. Adrenal weight and plasma corticosterone after tourniquet or ether stress were indistinguishable in the AH and H groups and were much higher and nearly identical in the intact, NH and IAH groups. We conclude that only the adenohypophysis secretes functionally significant amounts of ACTH. Plasma ACTH detected by the N-terminal antibody in the AH group is probably related to alpha-MSH or similar peptides and is incapable of maintaining adrenal weight or stimulating corticosterone secretion.
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PMID:Evidence that the pars intermedia and pars nervosa of the pituitary do not secrete functionally significant quantities of ACTH. 16 33

Adrenocorticotropic hormone (ACTH) inhibited [3H]thymidine incorporation in normal adrenocortical cells of adult rats in culture, with a concomitant increase in corticosterone production and a characteristic retraction of cells. Both dibutyryl cyclic AMP and an analog of ACTH, which produces virtually no cyclic AMP, inhibited DNA synthesis and stimulated steroid production. ACTH inhibited the proliferation of adrenocortical cells obtained from suckling rats as well as the cells obtained from the capsular tissue of adult rat adrenal glands, whereas insulin caused a stimulation of DNA synthesis. These results suggest that the major role of ACTH is to induce the transformation of the undifferentiated cells of the adrenal gland into functional fasciculata cells and that the proliferation of adrenocortical cells may be under control of factors other than ACTH.
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PMID:Inhibition of replication of normal adrenocortical cells in culture by adrenocorticotropin. 16 10

This report considers the potential usefulness of adrenocorticotropic hormone (ACTH) determinations in diagnosis and in prognosis for therapy of patients with carcinoma of the lung but without clinical Cushing's syndrome. The report is based on radioimmunoassay data from 129 patients, including 62 with lung cancers and 67 with nonmalignant pulmonary conditions. Elevated plasma ACTH was found in 21 of 24 patients with untreated cancer and the hormone was detected in tumor extracts and/or bronchial washings from the remaining 3. Elevation of plasma ACTH was found in only 10 of 38 treated patients. Absence of clinical Cushing's syndrome in spite of high plasma ACTH concentrations is explained by the observation that the predominant form of ectopic ACTH in plasma is immunoreactive but nonbioactive 'big' ACTH. Prolonged survival, for longer than 19 months, was observed in only 5 patients: all patients with low plasma ACTH after resection of the lung tumor and 2 of 3 patients with low plasma ACTH without therapy. ACTH was found in all available malignant tissue, primary and metastatic, from the lung carcinoma group,but not in normal lung or in 5 tumors metastatic to the lung. Of the 39 patients diagnosed initially to have chronic obstructive pulmonary disease, 14 showed plasma ACTH elevation. However, 3 of these patients with the highest concentrations subsequently manifested carcinoma or carcinoma in situ.
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PMID:Ectopic production of big ACTH in carcinoma of the lung. Its clinical usefulness as a biologic marker. 16 43

1. It was shown that the development of liver glucokinase in the rat coincided with a peak in the levels of circulating thyroid hormone at about the 16th postnatal day. 2. Administration of thyroid inhibitors blocked the development of the enzyme and administration of thyroid hormone restored activity to normal levels. 3. Glucokinase could be induced prematurely as early as the 2nd postnatal day by the administration of thyroid hormone followed by daily injection of glucose (10 mg/g body weight). 4. Glucocorticoids and corticotropin failed to induce glucokinase activity prematurely. 5. The postnatal increase in circulating thyroid hormone levels together with increased intake of carbohydrate at weaning may be the normal physiological stimulus for induction of this enzyme.
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PMID:Premature induction of glucokinase in the neonatal rat by thyroid hormone. 16 49

Three experiments examined the hypothesis that the effects of septal lesions and systemic injections of scopolamine on avoidance acquisition could be attributed to the effects of either of these treatments on adrenocorticotropic hormone (ACTH) secretion. Septal lesions and scopolamine facilitated 2-way conditioned avoidance response acquisition, and the lesions retarded passive avoidance acquisition. However, neither the injections of dexamethasone, a synthetic glucocorticoid which inhibited ACTH secretion as did septal lesions, nor injections of ACTH which mimicked the facilitatory effects of scopolamine on basal ACTH secretion, affected avoidance in these paradigms. Thus, the main hypothesis was not supported. The finding that scopolamine did not affect passive avoidance indicates that a cholinergic system may not be involved in mediating the suppressive effects of punishment.
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PMID:Role of pituitary-adrenocortical system in mediating avoidance behavior of rats with septal lesions. 16 87

Rats were given one training trial that was followed 2 days later by one test trial in a "step-out" passive avoidance task. Each rat was injected with either adrenocorticotropic hormone (ACTH) or placebo before training and before testing. Four groups of rats were used, representing the 4 possible training-testing injection combinations: placebo-placebo, placebo-ACTH, ACTH-placebo, and ACTH-ACTH. ACTH given in testing increased avoidance for subjects that had received ACTH in training and decreased avoidance for those that had received placebo in training.
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PMID:Effect of adrenocorticotropic hormone on conditioned avoidance in rats interpreted as state-dependent learning. 16 88

Tissue levels of bioactive and immunoactive ACTH were measured in both the anterior and neuro-intermediate lobes of the rat pituitary. Similar concentrations of bioactive (65 ng/mg) and immunoactive (83 ng/mg) ACTH were found in the anterior lobes control rats. A 2-min ether stress had no effect on either bioactive or immunoactive ACTH levels in the anterior lobe. Twenty-four h after adrenalectomy the anterior lobe content of both bioactive and immunoactive ACTH decreased only to return to supranormal levels 21 days after the operation. A 30-min neurogenic stress had no effect on anterior lobe bioactive ACTH content but reduced the immunoactive ACTH level to 50 ng/mg. Synthetic alphah-17-39 ACTH was used in our radio-immunoassay in order to measure the C-terminal ACTH activity of the neuro-intermediate lobe. The concentration of such C-terminal activity in control rats (890 ng alphah-17-39 ACTH/mg) considerably exceeded the amount of bioactive ACTH (15 ng/mg). This is presumably due primarily to the presence of the so-called corticotropin-like intermediate lobe-peptide (CLIP). The amounts of bioactive or C-terminal immunoactive ACTH in the neuro-intermediate lobe were not affected by ether stress nor short term (24-h) or long term (21-day) adrenalectomy. Neuro-intermediate lobe bioactive ACTH decreased (to 8 ng/mg) only with the introduction of a 30-min neurogenic stress. Neurogenic stress had no effect on the concentration of CLIP, but when the stress was imposed 24 h after adrenalectomy, a significant reduction was observed. The data support the presence of bioactive ACTH in the intermediate lobe of the rat pituitary and suggest that such ACTH is preferentially released by neurogenic stress and not appreciably regulated by circulating levels of glucocorticoids. Until the biological function and/or target organ of CLIP is identified, the significance of the changes in tissue levels of C-terminal immunoactive ACTH will remain unknown.
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PMID:Bioactive and immunoactive ACTH in the rat pituitary: influence of stress and adrenalectomy. 16 60

Glucagon activated adenylate cyclase in a homogenate of a pheochromocytoma over the concentration range 1 times 10 minus 8M to 1 times 10 minus 6M. Several other hormones including adrenocorticotropin, thyrotropin, parathyroid hormone and histamine were without effect. The tumor glucagon receptor was characterized and found to be similar in several ways to the glucagon receptor previously reported in normal tissue such as liver and heart. One, the receptor specifically bound 125-I-glucagon. Two, solubilization of the pheochromocytoma abolished glucagon-activation of the adenylate cyclase. Three, glucagon-responsiveness of the adenylate cyclase was partially restored by the addition of phosphatidylserine to the incubations. One major difference was observed between the glucagon receptor in tumor tissue and that in liver and heart, namely, a marked lability in 125-I-glucagon binding and adenylate cyclase activity. Within four days, despite storage in liquid nitrogen, 75% of the binding activity and all of the adenylate cyclase activity in the solubilized preparation were lost. The factor(s) responsible for this lability remains unidentified.
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PMID:Characterization of the glucagon receptor in a pheochromocytoma. 16 16

The effect of synthetic alpha-MSH injected intravenously in a uniform dose of 3 mg was studied in 19 prepubertal children. A marked growth hormone (GH) response was seen only in 2 out of 8 constitutionally small children with a normal GH response to insulin and arginine stimulation. Three of of 11 children suffering from hypopituitarism with documented GH and other hormone deficiencies, unexpectedly, showed a significant rise of GH after alpha-MSH: all three had craniopharyngiomas. Alpha-MSH led to an increase of plasma cortisol in all except 3 patients who had secondary adrenal insuffciency. The increase of cortisol after alpha-MSH and after insulin was of the same extent: but the hypoglycemia and stress responsible for the insulin effect were not observed after alpha-MSH. It is possible that alpha-MSH acts by an ACTH-like direct stimulation on the adrenals. There was no effect of alpha-MSH on plasma TSH or on blood glucose.
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PMID:The effect of alpha-MSH on plasma growth hormone, cortisol and TSH in children. 16 18


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