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)

Insulin-like growth factors (IGFs) are single-chain polypeptides important for cell proliferation and growth. IGFs are produced in several tissues, suggesting that they function in a paracrine or autocrine fashion as well as functioning as endocrine hormones. We studied the hormonal regulation of IGF-I and IGF-II mRNA in human steroidogenic tissues. In cultured human ovarian granulosa cells, follicle-stimulating hormone, human chorionic gonadotropin, and dibutyryl cAMP increased IGF-II mRNA, but corticotropin [adrenocorticotropic hormone (ACTH)], chorionic somatomammotropin, growth hormone, prolactin, dexamethasone, estradiol, and progesterone had no effect. In cultured human fetal adrenal cells, ACTH and dibutyryl cAMP increased IGF-II mRNA accumulation, but human chorionic gonadotropin and angiotensin II did not. The same five size species of IGF-II mRNA were detected in transfer blots of RNA from granulosa cells and fetal adrenal cells, and all of these increased after hormonal stimuli. Dibutyryl cAMP also increased IGF-II mRNA accumulation in cultured human placental cells. Accumulation of mRNA for the cholesterol side-chain-cleavage monooxygenase [P450scc [corrected]; cholesterol, reduced-adrenal-ferredoxin:oxygen oxidoreductase (side-chain-cleaving), EC 1.14.15.6] was regulated in parallel with IGF-II mRNA in all these steroidogenic tissues. IGF-I mRNA was not detected in transfer blots of these RNAs, and the minimal amounts detected in dot blots showed no detectable change after any of the hormonal stimuli studied. The data indicate that the IGF-II gene is expressed in human steroidogenic tissues and is regulated by cAMP. These data suggest that IGF-II may act in an autocrine or paracrine fashion to stimulate the adrenal and gonadal growth stimulated by ACTH and gonadotropins, respectively.
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PMID:Coordinate tropic hormone regulation of mRNAs for insulin-like growth factor II and the cholesterol side-chain-cleavage enzyme, P450scc [corrected], in human steroidogenic tissues. 303 44

The sand-rat (Psammomys obesus) is an animal model for the study of human maturity onset diabetes which appears to be controlled by caloric intake. In the present investigations, these animals have been studied in relation to the influence of low- and high-energy diets on body weight, plasma insulin and blood glucose levels, and on insulin secretion from the perfused pancreas and the secretion of corticotropin-like intermediate lobe peptide (CLIP, ACTH18-39) and the insulin secretagogue beta-cell-tropin (beta-CT, ACTH22-39) from the pituitary neurointermediate lobe. The sand-rats maintained on the high-energy diet all became obese. Insulin secretion from the perfused pancreas of the obese sand-rat in the presence of 5.6 mM glucose was significantly higher than in the lean controls maintained on low-energy diets. Increasing the glucose concentration to 16.7 mM only produced a small stimulation of insulin secretion in the obese animals, and the difference between the two groups was not significant. Stimulation of insulin secretion by beta-CT was variable, but the obese animals appeared to be more responsive. Pituitary neurointermediate lobes were incubated for 4 h to measure the secretion of the ACTH related peptide. These were separated by gel filtration and the concentrations measured by radioimmunoassay with a CLIP antiserum and a CLIP standard. In all experiments beta-CT was 4-6 per cent of the total CLIP immunoreactive material. In these experiments the obese animals maintained on a high-energy diet were divided into two groups, those with plasma insulin levels less than 500 mu u/ml and those with insulin levels greater than 500 mu u/ml. The latter group had a significantly higher blood glucose level, presumably due to the insulin resistance resulting from the severe hyperinsulinaemia. It was also observed that CLIP-IRM and beta-CT secretion was lower in this group than in the animals maintained on low-energy diets or those on high-energy diets with moderate hyperinsulinaemia. This suggests a possible feedback inhibition by insulin on the secretion of beta-CT.
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PMID:Studies on insulin secretion and the pituitary insulin secretagogue beta-cell-tropin in the sand-rat (Psammomys obesus). 303 19

The effects of the opiates beta-endorphin, dynorphin, met-enkephalin, leu-enkephalin, morphine and of the opiate-antagonist naloxone on glucose metabolism and lipolysis were studied in isolated rat adipocytes. None of the tested substances was found to alter 125I-Insulin binding. The opiates did not influence 2-deoxy-glucose uptake or glucose incorporation into lipids. They also did not exhibit a lipolytic activity. We conclude that the disturbances of glucose homeostasis induced by endogenous opiates are not mediated by an effect on peripheral glucose metabolism.
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PMID:Endogenous opiates do not influence glucose and lipid metabolism in rat adipocytes. 307 86

Insulin depresses both the activity of adenylate cyclase stimulated by glucagon, epinephrine, and sodium fluoride in liver cell membranes and the activity of adenylate cyclase stimulated by epinephrine and adrenocorticotropin in particulate preparations from homogenates of isolated fat cells. Significant inhibition is detected with very low concentrations (10(-11) molar) of insulin but not with unphysiologically high (10(-9)molar) concentrations of the hormone. These direct effects of insulin on an enzymatic system in broken-cell -preparations suggest a fundamental role of adenylate cyclase activity and of cyclic adenosine monophosphate in the mechanism of action of insulin.
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PMID:Modulation of adenylate cyclase activity in liver and fat cell membranes by insulin. 433 23

Epinephrine stimulated lipolysis and the uptake of oxygen by subcutaneous adipose cells of man. When glucose-(14)C was present in the medium, its utilization was not increased by epinephrine, although lipolysis was accelerated. Insulin did not reduce the production of fatty acids that had been stimulated by epinephrine. The combination of human growth hormone and cortisol stimulated the production of fatty acids by isolated human adipose cells to a lesser extent than epinephrine. When human growth hormone or cortisol was used singly, or when bovine growth hormone was added in combination with cortisol, no effect on fatty acid production was observed. Furthermore, an acetone-dried preparation of human pituitary glands, which was shown to stimulate lipolysis in rat adipose cells, had no effect on fatty acid formation in human adipose cells. This suggested that the human pituitary gland contained no more potent lipolytic agents than growth hormone and was supported by the lack of response of human adipose cells to purified corticotropin.
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PMID:Studies on lipolysis in human adipose cells. 602 Dec 10

Baseline plasma levels of beta-endorphin, beta-lipotropin, and ACTH were assayed in 37 patients with chronic schizophrenia: 24 men and 13 women, 28 with hebephrenic and nine with paranoid schizophrenia. None of the patients had received any medication for at least 10 days. The mean values of both opioids were significantly higher in the schizophrenic patients than in 21 age- and sex-matched control subjects. Insulin stimulation and dexamethasone suppression tests were given to eight of the patients, and the circadian rhythms of beta-endorphin, beta-lipotropin, ACTH, and cortisol were assayed in the same eight patients. Insulin stimulation, dexamethasone suppression test results, or circadian rhythmicity was impaired in seven of these eight patients.
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PMID:Secretion pattern of endogenous opioids in chronic schizophrenia. 609 63

A soluble somatostatin binding factor was detected in cell-free extracts from chicken pancreas. For binding measurements Tyr1-somatostatin was radio-labeled with 125I by the lactoperoxidase technique. Specific radioactivity of about 18.5 MBq/nmol was achieved. Maximal total binding is approximately 0.17 (B/T) in the presence of 30 mg/l pancreatic protein. The specific binding is 0.10 and is suppressed by addition of 1 mg/l synthetic cold cyclic somatostatin. The dose-response curve of synthetic cyclic somatostatin is in the range of 0.6-600 nmol/l. Ca2+ and reduced thiol-reagents inhibit the specific binding. Insulin, glucagon and corticotropin show a low, and luliberin and reduced somatostatin a high cross-reactivity. Molecular weight was estimated by gel filtration and the specific binding molecule was eluted at a Kav = 0.2 on an Ultrogel (AcA 54) column. This corresponds to Mr 40 000. Electrophoretic properties of the binding complex and semipurification by polyacrylamide disc gel electrophoresis: relative mobility of the 125I-Tyr-somatostatin binding complex is about 0.6. Relative mobilities of binding-protein fractions are 0.71 and 0.74. Highest relative specific binding was detected in the (100 000 g) cytosol fractions. Binding with cell-free extracts from the splenic lobe area was 4-fold higher than that from other parts of the chicken pancreas.
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PMID:Somatostatin binding factor from chicken pancreas. 611 81

The soluble guanylate cyclase activity of rat liver appears to be stimulated in VITRO by insulin at pMolar concentrations, while proinsulin, denaturated insulin or desoctapeptide insulin, are not able to stimulate the studied enzymic activity. Corresponding concentrations of other peptide hormones such as corticotropin (ACTH) or glucagon, either in the absence or in the presence of bacitracin, do not show any effect on the investigated enzymic system. Insulin stimulation of the soluble guanylate cyclase is characterized by a significant increase in the Vmax together with a decrease of the apparent Km. Insulin at low concentrations doesn't affect the cyclic GMP hydrolyzing activity; conversely higher concentrations of the hormone, while exerting a less marked effect on the guanylate cyclase activity, inhibit the cyclic GMP hydrolyzing activity.
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PMID:Low insulin concentrations stimulate in vitro the soluble guanylate cyclase activity of rat liver. 613 76

Incorporation of 3H-uridine by RNA in Tetrahymena was differently influenced by insulin, glucagon, follicle-stimulating hormone (FSH), thyrotropic hormone (TSH), adrenocorticotropic hormone (ACTH) and chorion-gonadotropic hormone (PMSG). TSH caused it to increase considerably and durably after an initial depression, while glucagon caused it to rise over the control throughout. Insulin, and especially PMSG, depressed the incorporation of label considerably, the latter to 3-6% of the control value by 120 min. ACTH and FSH accounted for an initial depression of RNA synthesis which, however, returned to normal 30 min after treatment. Remarkably, while the chemically similar hormones acted differently, insulin and glucagon showed the same trend of positive and negative influence, respectively.
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PMID:Effect of polypeptide hormones (insulin, thyrotropin, gonadotropin, adrenocorticotropin) on RNA synthesis in Tetrahymena, as assessed from incorporation of 3H-uridine. 618 2

Confluent 3T3-L1 fibroblasts incubated for 72 h with methylisobutylxanthine, dexamethasone, and insulin differentiate and acquire phenotypic characteristics of mature adipocytes, including hormone-sensitive cAMP phosphodiesterase activity located in a particulate fraction of homogenates. About 10 days after initiating differentiation, a maximally effective concentration of insulin (100 pM) increased particulate cAMP phosphodiesterase activity 40 to 60% in 8 min; activation persisted for at least 30 min in the presence of insulin. Incubation of adipocytes for 6-8 min with agents that increased cAMP, e.g. 1 microM epinephrine, 0.1 microM isoproterenol, corticotropin (2 mu units/ml), or thyroid-stimulating hormone (15 ng/ml), also increased particulate phosphodiesterase activity 40-60%. Changes in phosphodiesterase activity produced by epinephrine tended to lag behind changes in cAMP. Insulin, epinephrine, and corticotropin increased Vmax, not Km (0.5 microM), for cAMP. Particulate phosphodiesterase activity, solubilized with detergent, eluted in a single peak from DEAE-Bio-Gel. Insulin and epinephrine increased the activity eluted in this peak. Neither insulin nor lipolytic hormones increased activity in soluble fractions from differentiated cells or particulate or soluble fractions from undifferentiated cells. Incubation of adipocytes for 48 h with 1 microM dexamethasone prevented insulin-induced activation of the particulate phosphodiesterase and did not alter basal activity. After incubation for 72 h with 0.1 microM dexamethasone, insulin and epinephrine activation were abolished. These effects of dexamethasone on hormonal regulation of particulate phosphodiesterase activity could account for some of the so-called permissive effects of glucocorticoids on cAMP-mediated processes as well as the "anti-insulin" effects of glucocorticoids.
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PMID:Hormone-sensitive particulate cAMP phosphodiesterase activity in 3T3-L1 adipocytes. Regulation of responsiveness by dexamethasone. 619 Aug 11


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