Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This experiment was performed to determine if plasma glucose homeostasis is maintained in normal human volunteers during light exercise (40% maximal oxygen consumption [VO2 max]) when changes in insulin and glucagon are prevented. Hormonal control was achieved by the infusion of somatostatin, insulin, and glucagon. Glucose kinetics and oxidation rates were determined with stable isotopic tracers of glucose, and by indirect calorimetry. Two different rates of replacement of insulin and glucagon were used; in one group, insulin was clamped at 19.8 +/- 2.6 microU/ml (high-insulin group), and in the other group insulin was clamped at 9.2 +/- 1.3 microU/ml (low-insulin group). Glucagon was maintained at 261 +/- 16.2 and 124 +/- 6.4 pg/ml, respectively, in the high-insulin and low-insulin groups. Without hormonal control, plasma glucose homeostasis was maintained during exercise because the increase in glucose uptake was balanced by a corresponding increase in glucose production. When changes in insulin and glucagon were prevented, plasma glucose concentration fell, particularly in the high-insulin group. Glucose uptake increased to a greater extent than when hormones were not controlled, and glucose production did not increase sufficiently to compensate. The increase in glucose uptake in the hormonal control groups was associated with an increased rate of glucose oxidation. When euglycemia was maintained by glucose infusion in the hormonal control subjects, the modest increase in glucose production that otherwise occurred was prevented. It is concluded that during light exercise there must be a reduction in insulin concentration and/or an increase in glucagon concentration if plasma glucose homeostasis is to be maintained. If such changes do not occur, hypoglycemia, and hence exhaustion, may occur.
 ...
PMID:Role of changes in insulin and glucagon in glucose homeostasis in exercise. 286 53

Plasma glucose, insulin, glucagon and growth hormone responses to both oral glucose and iv arginine were evaluated in 15 heroin addicts and 15 control subjects matched for age, sex and weight. The heroin users had an exaggerated rise in plasma glucose concentrations following oral sugar, which persisted until the end of the study (102 +/- 5 mg/dl in addicts vs 72 +/- 3 mg/dl in controls at 240 min, p less than 0.01) and significantly lower insulin responses (insulin peak 28 +/- 4 microU/ml in addicts vs 67 +/- 8 microU/ml in controls, p less than 0.01). The inhibitory effect of glucose on glucagon concentrations was less evident in addicts than in controls. The responses of plasma glucose, insulin and glucagon to arginine were not significantly different between addicts and controls, while the growth hormone rise was significantly greater in addicts. These results demonstrate that heroin users have impaired insulin secretion to oral glucose but not to arginine and suggest that: the impaired insulin secretion in heroin addicts is not dependent on beta-cell exhaustion, and a selective inhibition of glucose-induced insulin secretion is operative in these subjects, as it happens in patients with noninsulin-dependent diabetes mellitus.
 ...
PMID:Impaired insulin response to glucose but not to arginine in heroin addicts. 354 79

Some acute and chronic metabolic effects of a new ACTH analogue (ACTH 1-17, Synchrodyn) were evaluated in healthy subjects and compared to those of the synthetic fragment ACTH 1-24. The peptides were injected at doses reportedly comparable with regard to their corticotropic effect, i.e. 100 micrograms ACTH 1-17 and 250 micrograms ACTH 1-24. A similar increase in blood glucose, NEFA and ketone bodies concentrations, without any significant modification of insulin, C-peptide and glucagon levels, was observed after injecting both peptides. The chronic treatment with ACTH 1-24 induced a significant increase in basal lactate, pyruvate and alanine blood concentrations. The levels of these metabolites resulted unaffected or slightly reduced after the corresponding treatment with ACTH 1-17. Our data are compatible with a certain degree of exhaustion of the adrenocortical reserve or, alternatively, a resetting of the circadian cortisol rhythm after prolonged treatment with the ACTH 1-17 analogue.
 ...
PMID:ACTH 1-17 effects on intermediary metabolites in healthy subjects. 609 Dec 41

Administration of insulin 1 i.u./100 g of body weight to hypothermic rats causes a fall of glucose and lactate levels in the serum and a rise in myocardial glycogen level in relation to the group of control rats kept at room temperature and to the group of rats subjected only to hypothermia. Beta-adrenergic blockade (propranolol 0.6-1 mg/kg) caused no changes in the levels of carbohydrate metabolites in the serum of hypothermic rats but raised the myocardial glycogen level by 42% in relation to the animals subjected only to hypothermia. Simultaneous administration of both these agents during hypothermia produces a fall of the serum levels of glucose and pyruvate with a rise in the level of lactate, and raises the glycogen level in the myocardium (by about 161%) and in the skeletal muscle (by 54%) in relation to the rats subjected to hypothermia alone. Insulin and/or propranolol fail to prevent glycogen reserve exhaustion in the liver of hypothermic rats which could be due to activation of non-blocked alpha-adrenergic receptors or to the action of yet another glycogenolytic agent, e.g. glucagon, during hypothermia.
 ...
PMID:Effects of insulin and beta-adrenergic blockade on certain indicators of carbohydrate metabolism in the blood and tissues of rats during short-lasting hypothermia. 613 94

During the past few years continuous ambulatory peritoneal dialysis (CAPD) has become well established in the home treatment of uremia. CAPD, however, may induce certain biochemical abnormalities. Using glucose as an osmotic agent of the dialysate the peritoneal glucose load may vary between 75 and 200 g per day, depending upon how often high osmotic dialysate is needed. If the latter is restricted to one bag per day a long-term disturbance of the glucoregulatory hormones insulin, GIP an glucagon seem to be inprobable. Investigations into glucose tolerance after 23 til 34 months of CAPD treatment in 4 patients did not indicate any exhaustion of the pancreatic beta-cells. Long-term evaluation into the metabolism of lipoproteins, total plasma proteins, aminoacids and trace elements did not show significant abnormalities induced by CAPD itself. Biochemical alterations observed are more or less related to the uremic state of the patients.
 ...
PMID:[Biochemical changes with continuous ambulant peritoneal dialysis (CAPD)]. 675 Sep 73

Selection for and against diabetes and subsequent inbreeding of Chinese hamsters started in 1963. Currently there are six inbred sublines that have greater than 85% incidence of glycosuria and two control inbred nondiabetic sublines that are essentially free of glycosuria. At birth, hamsters from inbred sublines are considered prediabetic. There is phenotypic variation between diabetic sublines. Onset time, incidence of ketonuria, blood glucose, plasma insulin, glucagon and glycohydrolase levels vary from subline to subline, but pancreatic insulin and glucagon levels are consistently low and high, respectively, in all diabetic sublines compared with nondiabetics. Experimental breeding data suggest a minimum of two homozygous recessive genes for diabetes. It is not known if the inbred lines are similar diabetic genotypes, but the probability is high that modifier background genes vary from subline to subline. Chinese hamsters have diabetes ranging from mild to severe. Animals weighing 25 g can excrete up to 75 ml of urine containing 3 g of glucose per day. Fasting blood glucose as high as 500 mg/dl and 10 mumol/ml of beta-hydroxybutyrate have been reported. Gluconeogenesis is elevated, and some glycolytic enzymes are decreased in severe diabetes. Low levels of renal acid glycohydrolase enzymes may contribute to glomerular capillary loop basement membrane thickening in diabetic hamsters. Caloric restriction per se or reduction of dietary fat prevented onset of hyperglycemia and hyperinsulinemia in prediabetics. Morphologic changes have been observed in pancreatic islets, kidney, nerve, blood vessels, eyes, brain, and genito-urinary systems of diabetic Chinese hamsters. Pathogenesis of diabetes in this animal appears to be related to an increased demand for insulin. Initially there is a positive response to this demand by beta cells, but exhaustion occurs. This is followed by a decrease in beta-cell mass and relative or absolute insulin deficiency.
 ...
PMID:The Chinese hamster as a model for the study of diabetes mellitus. 676 Nov 91

Seven aged subjects (mean age 78,5 years) and seven young controls (mean age 23,8 years), all nondiabetics and non-obese, were given intravenous injections of glucose, glucose and arginine, tolbutamide, tolbutamide and glucagon at 30 minutes intervals in order to determine the maximum insulin-secretory capacity of their pancreatic beta-islet cells after intensive stimulation. The response iun the elderly group was less prompt and quantitatively smaller at all stage of the test, but the beta-cells both in aged and in young subjects showed no evidence of exhaustion.
 ...
PMID:[Exhaustibility of beta cells in the aged after repeated stimuli]. 700 Dec 76

We have previously shown that adrenodemedullation combined with chemical sympathectomy decreases the exercise-induced muscular glycogen breakdown in rats. Now we have elucidated to what extent the effect of combined adrenodemedullation and sympathectomy can be ascribed to the lack of either the adrenal medulla or of the peripheral sympathetic nerve endings. Rats were either adrenodemedullated or underwent sham operation and subsequent unilateral hindleg sympathectomy. Three weeks after adrenodemedullation and 1 wk after sympathectomy, the rats either rested or swam with a tail weight for 75 min or continued swimming to exhaustion. The exercise-induced muscular glycogenolysis was markedly impeded by adrenodemedullation but not by sympathectomy. During the first 75 min of exercise, hepatic glycogenolysis was decreased in adrenodemedullated rats compared with sham-operated rats, and blood glucose only increased in the latter. At exhaustion, plasma insulin and glucagon were higher and lower, respectively, in adrenodemedullated rats than in sham-operated rats, whereas blood glucose did not differ significantly between these groups. During prolonged swimming in rats, adrenomedullary hormones enhance muscular glycogenolysis, glucagon secretion, and the early hepatic glycogenolysis but inhibit insulin secretion.
 ...
PMID:Control of exercise-induced muscular glycogenolysis by adrenal medullary hormones in rats. 700 27

Blood samples were taken before and immediately after 80 km and 40 km rides held on consecutive days and analysed for haematocrit, blood glucose and lactate, plasma sodium, potassium, calcium, albumin, free fatty acids (FFA), glycerol, bicarbonate, insulin, cortisol, glucagon, urea, creatinine, uric acid, bilirubin and alkaline phosphatase. Unusually hot weather probably contributed to haemoconcentration with a significant (P < 0.001) increase in haematocrit and plasma albumin. A fall in blood glucose, with a rise in FFA and glycerol were consistent with long distance riding and were associated with a reduction in plasma insulin and a rise in cortisol and glucagon. The results suggested that the horses were working aerobically and the small increase in blood lactate was likely to be a result of reduced tissue perfusion. Plasma urea, creatinine and bilirubin increased during the 80 km ride and were still high the next morning. Blood samples were taken from 2 horses that became exhausted and were forced to retire and the results from these animals indicate the slow rate of recovery. It is suggested that haemoconcentration with reduced tissue perfusion might contribute to exhaustion during long distance exercise and that the speed of recovery might be improved by the intravenous administration of balanced electrolyte solutions.
 ...
PMID:Further studies on the metabolic effects of long distance riding: Golden Horseshoe Ride 1979. 743 43

The purpose of this study was to examine the effects of ingesting water (P), a glucose solution (GL), a maltodextrin solution (Md), a glucose solution with 8% guar gum (GL+G), and a maltodextrin solution with 8% guar gum (Md+G), on the hormonal and metabolite responses during cycling, and on subsequent time to exhaustion. Five male subjects undertook five 90 min rides on a bicycle ergometer at an exercise intensity corresponding to 65% VO2max after having ingested 1 g.kg-1 body weight of the test product in 400 ml of water immediately before the exercise. Blood samples were taken during the trials for analyses of adrenaline, noradrenaline, insulin, glucagon, glucose, lactate and non-esterified fatty acids (NEFA). Respiratory measures were also undertaken during the trials for the determination of oxygen consumption (VO2) and respiratory exchange ratio (RER), from which the carbohydrate oxidation rates were calculated. Rates of perceived exertion (RPE) were also assessed. Ten minutes after the 90 min ride, subjects exercised to volitional exhaustion at an exercise intensity of 75% VO2max. ANOVA revealed that there were significant differences between the treatments for adrenaline (p < 0.01), insulin (p < 0.05), glucose (p < 0.01), lactate (p < 0.01), NEFA (p < 0.01), RER (p < 0.001) and carbohydrate oxidation rate (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Hormonal and metabolite responses to glucose and maltodextrin ingestion with or without the addition of guar gum. 789 Apr 59


<< Previous 1 2 3 4 5 6 7 Next >>