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

In perifused isolated pancreatic islets alpha-ketoisocaproic acid (KIC) or alpha-ketocaproic acid (KC) induced a high insulin secretion rate and a steep increase of the fluorescence of reduced pyridine pyridine nucleotides [NAD(P)H] which fell again to almost prestimulatory levels 6 min after medium change. Insulin release in response to alpha-ketooctanoic (KO) acid started slowly and was accompanied by a decrease of the NAD(P)H-fluorescence trace. Beta-phenylpyruvate which is known to initiate insulin release also caused a fluorescence decrease. Alpha-keto-isovaleric (KIV) acid or pyruvate had no significant effects upon insulin secretion or NAD(P)H-fluorescence. In contrast to l-leucine, l-norleucine or l-valine did not enhance insulin release or fluorescence of NAD(P)H. KIV, alpha-keto-beta-methylvaleric acid (KMV), KIC and KC raised the production their corresponding amino acids by islet cells. From these results it is concluded that alpha-ketomonocarboxylic acids as such trigger insulin release by acting upon receptor sites which differ from those occupied by amino acids.
 ...
PMID:Effects of alpha-ketomonocarboxylic acids upon insulin secretion and metabolism of isolated pancreatic islets. 0 87

Diabetic ketoacidosis is an acute medical emergency that requires immediate diagnosis and treatment. Diagnosis may be established rapidly by measurement of urinary glucose and ketones, arterial blood pH and blood gases, and serum ketones. Rapid infusion of large volumes of fluids and electrolytes, together with continuous infusion of low doses of insulin, provides effective restoration of fluid and electrolyte balance and correction of metabolic derangements. Hyperosmolar nonketotic coma is characterized by marked hyperglycemia in the absence of ketoacidosis and occurs usually in patients with mild adult-onset diabetes. Symptoms develop more slowly than in diabetic ketoacidosis. Treatment is the same for both conditions. In alcoholic ketoacidosis, hyperketonemia is present without hyperglycemia. The syndrome differs from diabetic ketoacidosis in that blood glucose levels are lower and glycosuria is absent. Treatment consists of intravenous administration of dextrose in water and, if necessary, of sodium bicarbonate. Insulin administration usually is not necessary.
 ...
PMID:Combating diabetic ketoacidosis and other hyperglycemic-ketoacidotic syndromes. 0 17

Water soluble pig insulin (4 x 10(-8) to 4 x 10(-7) g/ml) produced a marked and long-lasting increase in the contractile force of the rabbit auricle in vitro. Once the maximum effect for a given insulin concentration had been reached, addition of more insulin did not produce any further increase in inotropic effect. Insulin was without effect in reserpinized animals. Inhibition of cardiac beta-receptors by propranolol suppressed the positive inotropic effect of insulin. These findings support the hypothesis that insulin releases catecholamines from the myocardium.
 ...
PMID:Positive inotropic effect of insulin on rabbit auricle in vitro. 0 25

Administration of hydrocortisone or insulin and also a simultaneous use of these hormones in a high dose caused a marked elevation of the total activity of tyrosine-alpha-ketoglutaric transaminase and its anode and cathode isoenzymes in the soluble fraction of the liver in the sexually immature (weighing 100-110 g) and mature (weighing 180-200 g) male rats. The stimulating effect of insulin was sharper in the young in comparison with adult animals. Administration of hydrocortisone caused a more pronounced elevation of the total tyrosine-alpha-ketoglutaric transaminase activity in the hepatic mitochondria of young rats than in adult animals. Insulin administration increased the activity of tyrosine-alpha-ketoglutaric transaminase in the mitochondria of the liver of the sexually mature male rats without significant changes of this enzyme in the sexually imature rats. A simultaneous injection of hydrocortisone and insulin to the sexaully mature male rats caused the same increase in the tyrosine-alpha-ketoglutaric transaminase activity in the hepatic mitochondria as after the administration of glucocorticosteriod alone. As to the sexaully immature males, the activity of the enzyme fell to the normal level. It is supposed that androgens played a significant role in the realization of the inducing action of glucocorticoids and insulin influencing the synthesis of tyrosine-alpha-ketoglutaric transaminase in different directions in the mitochondria of the liver of young and sexually mature animals.
 ...
PMID:[The effect of hydrocortisone and insulin on the activity and isoenzymes of typrosine-alpha-ketoglutarate transaminase in the ctyostructures of the livers of rats of different ages]. 0 78

Isoenzymes NAD-and NaDP MDH were detected in the cardiac muscle of rabbits by disc electrophoresis in polyacrylamide gel. Alloxan diabetes proved to be accompanied by a significant reduction in the activity of mitochondrial NADP MDH (in the reaction of malic decarboxylation) and its increase in cytozol. The activity of NAD-MDH (in the reaction of oxyacetate reduction) was also decreased in various isoenzymes in the myocardium (particularly in the mitochondria) in diabetes. Insulin restored the correlation of the activities of the isoenzymes NAD- and NADP-MDH in the cytostructures of the myocardium disturbed in diabetes.
 ...
PMID:[Activity of NAD- and NADP-dependent malate dehydrogenase isoenzymes in the myocardium of rabbits with alloxan diabetes]. 0 94

Sequential determinations of glucose outflow and inflow, and rates of gluconeogenesis from alanine, before, during and after insulin-induced hypoglycemia were obtained in relation to alterations in circulating epinephrine, norepinephrine, glucagon, cortisol, and growth hormone in six normal subjects. Insulin decreased the mean (+/-SEM) plasma glucose from 89+/-3 to 39+/-2 mg/dl 25 min after injection, but this decline ceased despite serum insulin levels of 153+/-22 mul/ml. Before insulin, glucose inflow and outflow were constant averaging 125.3+/-7.1 mg/kg per h. 15 min after insulin, mean glucose outflow increased threefold, but then decreased at 25 min, reaching a rate 15% less than the preinsulin rate. Glucose inflow decreased 80% 15 min after insulin, but increased at 25 min, reaching a maximum of twice the basal rate. Gluconeogenesis from alanine decreased 68% 15 min after insulin, but returned to preinsulin rates at 25 min, and remained constant for the next 25 min, after which it increased linearly. A fourfold increase in mean plasma epinephrine was found 20 min after insulin, with maximal levels 50 times basal. Plasma norepinephrine concentrations first increased significantly at 25 min after insulin, whereas significantly increased levels of cortisol and glucagon occurred at 30 min, and growth hormone at 40 min after insulin. Thus, insulin-induced hypoglycemia in man results from both a decrease in glucose production and an increase in glucose utilization. Accelerated glycogenolysis produced much of the initial, posthypoglycemic increment in glucose production. The contribution of glycogenolysis decreased with time, while that of gluconeogenesis from alanine increased. Of the hormones studied, only the increments in plasma catecholamines preceded or coincided with the measured increase in glucose production after hypoglycemia. It therefore seems probable that adrenergic mechanisms play a major role in the initiation of counter-regulatory responses to insulin-induced hypoglycemia in man.
 ...
PMID:The role of adrenergic mechanisms in the substrate and hormonal response to insulin-induced hypoglycemia in man. 0 91

Significant alterations in heart carbohydrate and lipid metabolism are present 48 h after intravenous injection of alloxan (60 mg/kg) in rats. It has been suggested that uncoupling of oxidative phosphorylation occurs in the alloxanized rat heart in vivo, whereas normal oxidative metabolism has been demonstrated in alloxan-diabetic rat hearts perfused in vitro under conditions of adequate oxygen delivery. We examined the hypothesis that high-energy phosphate metabolism might be adversely affected in the alloxan-diabetic rat heart in vivo. Phosphocreatine and ATP were reduced by 58 and 45%, respectively (P is less than 0.001). Also, oxygen-dissociation curves were shifted to the left by 4 mmHg, and the rate of oxygen release from blood was reduced by 21% (P is less than 0.01). Insulin administration normalized heart high-energy phosphate compounds. ATP production was accelerated in diabetic hearts perfused in vitro with a well-oxygenated buffer. These studies support the hypothesis that oxidative ATP production in the alloxan-diabetic rat heart is reduced and suggest that decreased oxygen delivery may have a regulatory role in the oxidative metabolism of the diabetic rat heart.
 ...
PMID:Reduced high-energy phosphate levels in rat hearts. I. Effects of alloxan diabetes. 0 45

Insulin and glucagon degradation by rat kidney homogenates and subcellular fractions was examined under a variety of conditions including high and low substrate concentrations, at pH 4 and pH 7, with and without glutathione. At high insulin concentration (4.1 - 10(-5) M) insulin degradation by the homogenate was greatest at pH 4 but at low insulin concentration (1 - 10(-10) M) insulin degradation was greatest at pH 7. At either high or low glucagon concentration glucagon degradation by the homogenate was greatest at pH 7. Glutathione at pH 7 stimulated insulin degradation at high insulin concentrations and inhibited insulin degradation at low concentrations; Glucagon degradation at pH 7 was inhibited at both high and low concentrations of glucagon by glutathionemseparation of kidney into cortex and medulla prior to homogenation produced a pattern of insulin and glucagon degradation identical to the whole homogenate but glucagon degradation by the medulla was greater than by the cortex. Examination of degradation by subcellular fractions revealed that at high concentration at neutral pH most insulin was degraded by the 100 000 X g pellet but at low insulin concentrations over 90% of the activity was in the 100 000 X g supernatant; At pH 7, at both high and low concentrations, most glucagon-degrading activity was in the 100 000 X g pellet, although the cytosol also had activity; At pH 4 most degradation occurred in the lysosomal fractions. Separation into cortex and medulla again showed similar distribution of activity as the whole gland with the medulla having more glucagon-degrading activity than the cortex. With low insulin concentrations the cortex 100 000 X g supernatant had higher relative specific activities than the medulla supernatant. Examination of recoveries of enzyme activity revealed that the subcellular fractions consistently had markedly less insulin-degrading activity than the original homogenate. This loss of activity was only discernible when insulin degradation was performed at pH 7 at low substrate concentrations. Comparable losses of glucagon-degrading activity were not seen.
 ...
PMID:Insulin and glucagon degradation by the kidney. I. Subcellular distribution under different assay condition. 0 5

The effect of insulin-induced hypoglycemia on the blood levels of catecholamines and renin activity has been studied in five patients with moderate hypertension before and after treatment for 3 - 8 months with penbutolol (PEN) 20 - 30 mg twice daily. Penbutolol caused no change in fasting blood glucose level. Insulin o.1 IU per kg body weight i.v. reduced blood glucose concentration by approximately 50 per cent after 30 - 45 min, both before and during treatment with penbutolol. Hypoglycemia prior to medication was accompanied by a marked increase in the production of adrenaline and a minor increase of noradrenaline in all five patients. During treatment the response of adrenaline to hypoglycemia was reduced in four patients and the data was inconclusive in one. Basal renin activity was rather low in three patients, within the normal range in one and relatively high in one. Before penbutolol the hypoglycemia-induced increase in catecholamine production caused no change in plasma renin activity in the three patients with low basal levels, whereas a marked increase was observed in the other two. During medication plasma renin activity remained unchanged on induction of hypoglycemia regardless of the catecholamine response. Despite the marked increase in plasma adrenaline following insulin-induced hypoglycemia, no statistically significant increase in pulse rate was recorded.
 ...
PMID:Long term treatment of moderate hypertension with penbutolol (Hoe 893d). II. Effect on the response of plasma catecholamines and plasma renin activity to insulin-induced hypoglycemia. 0 1

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.
 ...
PMID:Effect of hypophysectomy and insulin on lipogenesis in cockerels. 1 Feb 39


1 2 3 4 5 6 7 8 9 10 Next >>