Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: HUMANGGP:034761 (insulin)
 211,843 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The binding of biologically active [125I]thyrotropin to purified plasma membranes prepared from bovine thyroid glands was studied. At 4 degrees C, specific binding reached a maximum after 2 h of incubation and a plateau was maintained for up to 20 h. Degradation of [125I]thyrotropin was undetectable after 2 h of incubation and was only 10% of the total after 20 h. At pH 6.0, at which binding was maximal, a single class of binding sites, having a dissociation constant of approx. 25 nM, was evident. Dissociation studies revealed first order kinetics with a half-time of 2-3 min. At pH 7.5, binding curves were complex, suggesting two orders of binding sites with dissociation constants of approx. 200 nM and 80 pM. Further, at this pH, dissociation of the thyrotropin from its receptor was also complex, suggesting the presence of two first order reactions, one with a half-time similar to that seen at pH 6.0 and another with a half-time of 4 h. At both pH 6.0 and 7.5, insulin, glucagon, growth hormone, and prolactin were without effect on [125I]thyrotropin binding. Similar high affinity and low affinity binding sites were seen with porcine thyroid membranes, but only low affinity sites were seen with either rat liver membranes or human cultured lymphocytes.
Biochim Biophys Acta 1976 Sep 21
PMID:The interaction of radioiodinated thyrotropin with plasma membranes. Evidence for high affinity binding sites in the thyroid. 0 55

Hypophysectomy increases hepatic lipogenesis in cockerels. In an attempt to find the possible hormonal mechanism for this we have examined the effects of hypophysectomy, insulin and pituitary homogenates on hepatic lipogenesis. Insulin (5 U/kg) injected intravenously, simultaneously with glucose-14C tracer, increased the amount of 14C found in liver lipids at 30 min after the injection. Similarly, insulin injected 5 min before killing, increased the incorporation of glucose-14C and acetate-14C by liver slices during a 30 min incubation. Hypophysectomy increased lipogenesis within 24 hours. The effect of insulin was most pronounced in hypophysectomized cockerels. The activity of the lipogenic enzyme, acetyl CoA carboxylase was similarly affected. A homogenate of chicken pituitaries added to the medium reduced lipid synthesis from glucose-14C by liver slices. This effect was larger in liver slices in which lipogenesis had been stimulated by insulin. The increased rate of hepatic lipgenesis in hypophysectomized cockerels may be caused partly by increased hepatic sensitivity to the lipogenic action of insulin or by the removal of a direct inhibition by pituitary hormones.
Horm Metab Res 1976 Sep
PMID:Effect of hypophysectomy and insulin on lipogenesis in cockerels. 1 Feb 39

In order to evaluate the metabolic response of nutritionally deprived cancer patients to parenteral nutrition, metabolic parameters including glucose turnover, oxidation, and Cori cycle activity were measured in eight patients before and during short-term (5 to 10 days) i.v. nutrition, with solutions containing amino acids and hypertonic glucose. Before parenteral nutrition, five patients had essentially normal glucose turnover, oxidation, and Cori cycle activity, whereas three patients had moderately increased glucose turnover and markedly increased Cori cycle activity. In response to parenteral nutrition, plasma glucose, insulin, and venous lactate concentration increased and free fatty acid decreased. The percentage of respiratory CO2 from glucose oxidation and the rate of oxidation increased. CO2 production increased, whereas O2 consumption was essentially unchanged. Respiratory quotient rose to greater than 1.0. Endogenous glucose production and high basal Cori cycle activity were decreased. Total parenteral nutrition was judged clinically beneficial in five patients, whereas one patient was unchanged. Deleterious responses, including moderate lactic acidemia, occurred in two of three patients with elevated basal Cori cycle activity.
Cancer Res 1977 Sep
PMID:Metabolic response to total parenteral nutrition in cancer patients. 1 78

Inhibition of glucose-stimulated insulin release by exogenous insulin has been demonstrated in pancreatic islets to be associated with a decrease of the NADPH/NADP ratio and the pentose-phosphate cycle activity. Batches of five islets were incubated for 15 and 90 minutes in 1 ml. of KRB buffer with 2 per cent albumin containing 3 mg./ml. glucose and 0, 200, 400, or 800 microU./ml. of rat insulin, and the glucose-6-phosphate (G6P) and 6-phosphogluconate (6PG) contents were determined by enzymatic cycling. In response to a rise in the concentration of insulin, the 6PG/G6P ratio decreased. A close relationship was observed between this decrease of 6PG/G6P ratio and the net insulin release, the absolute rate of glucose oxidation via the pentose phosphate cycle, and the NADPH/NADP ratios measured under similar conditions. The results suggest that exogenous insulin, directly or indirectly, regulates the pentose cycle activity in the pancreatic islets at the G6P dehydrogenase step.
Diabetes 1977 Sep
PMID:6-Phosphogluconate/glucose-6-phosphate ratio in rat pancreatic islets during inhibition of insulin release by exogenous insulin. 1 30

Metabolic and cardiovascular responses to selective beta-adrenergic bronchodilators, carbuterol and metaproterenol, were studied during an asymptomatic period in 8 male subjects with bronchial asthma diagnosed as mile to moderate. On separate days each individual received either placebo, carbuterol 2 mg, carbuterol 4 mg, or metaproterenol 20 mg orally in a double-blind fashion. Subsequently, metabolic and cardiovascular responses were measured periodically for 5 hr. Carbuterol 2 mg was indistinguishable from placebo except for small elevations of glucose at 3 and 4 hr. Carbuterol 4 mg produced significant increases in glucose, insulin, lactate, and free fatty acids as well as in pulse rate and arterial pulse pressure. Metaproterenol produced increases only in plasma glucose and insulin. The majority of patients reported drug-related side effects which were all mild, after taking either carbuterol 4 mg or metaproterenol 20 mg. Fewer subjective side effects were noted with carbuterol 2 mg. These findings indicate that a 2-mg dose of carbuterol can be administered to typical asthmatic subjects without significant subjective or objective side effects. The larger dose (4 mg) may be accompanied by a greater frequency of side effects.
J Allergy Clin Immunol 1977 Sep
PMID:Metabolic and cardiovascular effects of carbuterol and metaproterenol. 1 14

1. A factor, which amplifies the inductions of several liver enzymes by glucocorticoid, was partially purified from Proteus mirabilis from rat intestine. The factor (amplifier) was completely inactivated by alpha-glucosidase, but not by other glycoside hydrolases, proteases, nucleases or phosphatases tested; it was also hydrolysed by HCl with liberation of reducing sugars. Thus the oligosaccharide in this factor seems to be essential for the amplification. 2. In adrenalectomized rats the amplifier increased the inductions of several liver enzymes, such as tyrosine aminotransferase and leucine aminotransferase, by glucocorticoid. But it did not amplify the induction of tyrosine aminotransferase by glucagon or insulin or the activities of enzymes that are not induced by glucocorticoid. The amplifier by itself did not have any glucocorticoid-like action in adrenalectomized rat. These results show that the amplifier specifically increases the inductions of liver enzymes by glucocorticoid. 3. Since similar amplification was also observed in isolated perfused liver and cultured hepatoma cells in vitro, the amplifier seems to act directly on the target organ or cells.
Eur J Biochem 1977 Sep
PMID:A new factor from enteric bacteria of rats amplifying induction of liver enzyme by glucocorticoid. 1. Purification, properties and biological action. 2 Oct 83

Plasma insulin concentrations in cold-adapted rats were altered acutely by administration of glucose or anti-insulin serum. Rates of fatty acid synthesis in interscapular brown adipose tissue were determined from the incorporation of 3H from 3H2O into tissue lipid. Rates of synthesis were greatly elevated after glucose administration and markedly decreased after injection with anti-insulin serum. Parallel changes in the initial activities of both acetyl-CoA carboxylase and pyruvate dehydrogenase were observed under these conditions, but no changes in total activities were evident. The results suggest that this tissue is an important site of fatty acid synthesis in the cold-adapted rat and that this feature of the tissue is sensitive to changes in plasma insulin concentrations.
Biochem J 1977 Sep 15
PMID:Evidence that fatty acid synthesis in the interscapular brown adipose tissue of cold-adapted rats is increased in vivo by insulin by mechanisms involving parallel activation of pyruvate dehydrogenase and acetyl-coenzyme A carboxylase. 2 6

Hyperglycemia and impaired glucose tolerance are well known phenomena occurring in patients with renal failure. In contrast to true diabetic subjects, an elevated ratio of insulin to glucose during the glucose tolerance test is consistently observed indicating a peripheral insulin insensitivity. Among the possible reasons, a disturbance at the cellular level seems to be most likely. There is some evidence of reduced peripheral glucose utilization on the one hand and increased hepatic glucose output--probably by stimulation of gluconeogenesis--on the other. Agents that have been suggested to be involved in these alterations of carbohydrate metabolism in uremia are hormones, electrolytes, pH, and "toxic" metabolic intermediates or end-products. Of these, an increase in insulin antagonistic hormones; among them growth hormone, catecholamines, and glucagon, seems to be of most significance. Although for the individual hormones no equivocal correlation with glucose intolerance has been proved, the interaction of all of them may result in a preponderance of insulin antagonism thus leading to an apparent insulin resistance.
Am J Clin Nutr 1978 Sep
PMID:Carbohydrate metabolism in renal failure. 2 64

Isolated spontaneously beating atria from streptozocin diabetic rats were compared with those from controls. Diabetic atria were found to have reduced rates, increased forces of contraction and reduced sensitivity to the inotropic effects of noradrenaline, isoprenaline, tyramine and calcium. Positive chronotropic responses to tyramine were also reduced but those to noradrenaline and isoprenaline were increased suggesting that tyramine releasable stores of noradrenaline were reduced. Elevation of glucose concentration in the medium from 5.6 to 27 mM resulted in decrease of inotropic sensitivity to the agents used in both control and diabetic rat atria. Resting contractile force of control rat atria was reduced by the inclusion of either 22 mM 2-deoxyglucose, 10(-3) i.u. insulin ml-1 or 5 mM acetate in the medium. The rate was also reduced by medium containing 2-deoxyglucose but increased by insulin. 2-Deoxyglucose also reduced inotropic but increased chronotropic sensitivity to isoprenaline. Possible mechanisms responsible for the changes observed are discussed.
J Pharm Pharmacol 1978 Sep
PMID:Comparison between spontaneously beating atria from control and streptozocin-diabetic rats. 2 94

Diaphragms from rats under 24-h-old did not show the well-known increased transport of alpha-aminoisobutyrate found in older tissues in respone to insulin in vitro. A small effect was apparent by 3 days, and stimulation increased as donor rats aged (up to 4--5 wk). One-day diaphragms also had greater uptake than older tissues, due to both decreased Km and elevated Vmax. The change in insulin sensitivity did not result from alteration in the transport system used by alpha-aminoisobutyrate because uptake showed characteristics of the A system at both 1 day and older. Results suggest instead that the 1-day tissues had been made insulin-resistant by high insulin levels in donor animals. Plasma insulin levels of 1-day-old rats were 5 times those of 5-day animals. Elevating the plasma insulin levels of 5-day or 25- to 35-day rats led to a decreased effectiveness of insulin in vitro in stimulating alpha-aminoisobutyrate transport into their diaphragms. In the older animals, the stimulation was inversely proportional to the plasma insulin level 2 h after insulin injection.
Am J Physiol 1978 Sep
PMID:Amino acid transport in diaphragms from newborn rats: evidence for insulin resistance. 2 88


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