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

Hormone-sensitive lipase and cholesterol ester hydrolase of chicken adipose tissue were markedly activated by adenosine 3':5'-monophosphate (cAMP)-dependent protein kinase (on the average, 235 to 275%; occasionally as much as 1000%). Diglyceride and monoglyceride hydrolases were also activated, but to a lesser extent (60 to 87%). The activation of all four hydrolases was inhibited by protein kinase inhibitor and reversed by the addition of exogenous protein kinase. Following activation by cAMP-dependent protein kinase, all four hydrolases were deactivated in a Mg2+-dependent reaction and then reactivated to or near initial levels on incubation with cAMP and Mg2+-ATP. The reversible deactivation is assumed to reflect activity of one or more protein phosphatases. The maximum activation obtainable for the four hydrolases decreased when the tissue had been previously exposed to glucagon, indicating that the glucagon-induced activation was probably similar to or identical with the activation demonstrated in cell-free preparations. The pH optima for the four hydrolase activities were similar (7.13 to 7.38). Although the absolute activities and relative degrees of kinase activation differed according to the particular emulsified substrates used, the results do not rule out the possibility that all four hydrolase activities are referable to a single hormone-sensitive hydrolase. Hormone-sensitive acyl hydrolases were separated from lipoprotein lipase by heparin-Sepharose affinity chromatography. Lipoprotein lipase was active against triolein, diolein, and monoolein, but not cholesterol oleate. Incubation of lipoprotein lipase with exogenous protein kinase, cAMP, and Mg2+ATP had no effect on any of the three hydrolase activities. Lipoprotein lipase was further purified to homogeneity and used to prepare antiserum in rabbits. The immunoglobin G fraction from these antisera completely inhibited lipoprotein lipase eluted from heparin-Sepharose columns. However, the hormone-sensitive hydrolase activities (not retained on heparin-Sepharose affinity chromatography) were not inhibited by anti-lipoprotein lipase immunoglobin G, and anti-lopoprotein lipase immunoglobin G did not affect the activation process in crude fractions. Thus, hormone-sensitive lipase and lipoprotein lipase, functionally distinct enzymes, have been physically resolved and immunochemically distinguished. Apparently lipoprotein lipase activity is not regulated, at least directly, by cAMP-dependent protein kinase.
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PMID:Triglyceride, diglyceride, monoglyceride, and cholesterol ester hydrolases in chicken adipose tissue activated by adenosine 3':5'-Monophosphate-dependent protein kinase. Chromatographic resolution and immunochemical differentiation from lipoprotein lipase. 0 45

An adenylate cyclase activity (AC) was found in guinea pig brown adipose tissue (BAT), since the tissue's apparition. This enzymatic activity increased during the development and showed high values at the end of gestation. An increase of AC units per cell was observed, in addition to the cell multiplication. A norepinephrine stimulation of AC activity was observed at the end of gestation : this regulating action disappeared in the first days of extrauterine life. Neither glucagon nor ACTH had any regulating role upon AC activity during fetal and newborn life. The basal lipolytic activity which was observed in BAT of fetuses (61rst day) and neonate dramatically around the 15th day. A potent lipolysis activation by norepinephrine was observed, but only after birth. The correlation observed between these enzymatic activities in presence of norepinephrine seems to indicate that the AC/lipase system was involved in the neonatal thermogenesis of guinea pigs.
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PMID:[Adenylate cyclase/Lipase. Hormone receptor induction]. 17 89

Plasma lipids and lipoproteins were studied in a group of chronic uraemia patients some of whom were maintained by regular haemodialysis. Compared with healthy individuals, there was a significant increase in plasma triglycerides and in the prebeta-1- and prebeta-2-lipoprotein plasma concentrations. There was no difference between dialyzed and undialyzed patients. Carbohydrate intake was normal, basal plasma insulin and free fatty acid levels were within the normal range. There was no correlation between plasma triglyceride levels and the degree of hypoalbuminaemia, the latter being marked in 30% of the patient. Basal plasma glucagon levels were very high in nearly all dialyzed patients and post-heparin lipoprotein-lipase activity was very low in dialyzed patients. In our experience, regular haemodialysis for 32 weeks did not improve hypertriglyceridaemia.
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PMID:Lipids and lipoproteins in chronic uraemia. A study of the influence of regular haemodialysis. 17 95

Lipoprotein-lipase activity was determined in tissue from the skeletal muscle of the leg and the subcutaneous adipose tissue of the abdomen in fourteen patients before and after 1 month of clofibrate administration. The concentrations of serum triglycerides decreased by, on the average, 37% in a group of thirteen patients which mainly consisted of subjects with type-IV hyperlipoproteinaemia. Clofibrate administration was associated with an average increase of the skeletal muscle-tissue lipoprotein-lipase activity of 50% (P less than 0.005). There was a significant correlation between the percentage changes in skeletal muscle-tissue lipoprotein-lipase activity and those of the triglycerides concentrations and the K2-values in an intravenous fat tolerance test during clofibrate treatment. Adipose-tissue lipoprotein-lipase activity did not change significantly. One patient with type-I hyperlipoproteinaemia had very low values of skeletal muscle-tissue lipoprotein-lipase activity and moderately low adipose-tissue lipoprotein-lipase activity. In this patient, neither the tissue lipoprotein-lipase activity nor the triglycerides concentration changed during clofibrate therapy. Fasting serum insulin concentrations decreased significantly during clofibrate administration and the percentage decrease was significantly correlated to the percentage increase of skeletal-muscle lipoprotein-lipase activity. It is suggested that the lowering of insulin levels is a possible mechanism through which glucagon activity is enhanced and this may increase skeletal muscle-tissue lipoprotein-lipase activity.
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PMID:Increase of the lipoprotein-lipase activity in human skeletal muscle during clofibrate administration. 41 37

Metabolic studies of a 9-year-old girl with primary type V hyperlipoproteinemia demonstrated normal glucose tolerance, plasma insulin and glucagon responses to stimuli, and serum uric acid level. Fasting plasma triglyceride levels rapidly increased when the patient received a diet containing 40% of the total calories as fat and rapidly decreased on a 10% fat diet. Hepatic and nonhepatic lipase activities in postheparin plasma were normal, thus excluding type I hyperlipoproteinemia. Because of the potential complication of acute pancreatitis in this disorder, early diagnosis and prompt institution of diet therapy is important.
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PMID:Primary type V hyperlipoproteinemia in childhood. 57 87

The subject of investigations was the influence of some endogenic substances: ions (K+ and Ca++), amines (serotonin, histamine and acetylcholine) and hormones (hydrocortisone and glucagon) on the lipase release from pancreatic granules (zymogen and lysosomes) of control and irradiated rats (800 R=24 hours). The decrease of enzyme release under the influence of hydrocortisone (both concentrations: 10(-6) and 10(-8) M), Ca++ ions, serotonin, histamine and acetylcholine after their administration in greater concentration (10(-6) M) was stated. Smaller concentrations of these substances evoked the transitory enhancement of enzyme activity. K+ ions and glucagon increased the lipase release (both concentrations). In the fraction of organelles from irradiated rats the action of K+ ions, glucagon and acetylcholine was diminished or abolished, while the inhibitory effectiveness (of greater concentrations) of Ca++ ions, serotonin, histamine and hydrocortisone was maintained.
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PMID:Investigations on the modification of postirradiation pancreatic lipase activity by some endo- or exogenic factors. Part II. The influence of some ions, biogenic amines and hormones. 66 54

Sixteen healthy subjects, 7 females and 9 males, with a mean age of 25 years (range 22--29 years), were studied in the fasting state in the morning and 8 h later after partaking of breakfast, lunch and two small meals. The lipoprotein-lipase activity in the adipose tissue increased significantly from 80 +/- 32 to 117 +/- 61 nmol fatty acid released per gram and minute (nmol FA/g/min), whereas in skeletal-muscle tissue it decreased significantly from 25 +/- 11 to 17 +/- 9 nmol FA/g/min. The concentration of serum triglycerides increased significantly from 0.93 +/- 0.18 mmol/l (mean +/- SD) in the fasting state to 1.57 +/- 0.64 mmol/l in the fed state. In the fasting state the lipoprotein-lipase activity of skeletal muscle was inversely related to the ratio between the concentrations of insulin and glucagon.
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PMID:Lipoprotein-lipase activity in human skeletal muscle and adipose tissue in the fasting and the fed states. 67 12

CFY male rats anaesthetized with pentobarbital were used in different groups for inducing acute pancreatitis by the retrograde injection either of 1 mg elastase, 5 mg trypsin, 4 mg lysolecithin, 10 mg Na-taurocholate in 0.2 ml volume or of 0.3 m. sunflower oil. In each group laparatomized animals served for control. The animals with pancreatitis were treated either with 15 mug/b.w.kg/hour glucagon or with physiological saline for 72 hours. Twenty-four and 72 hours after inducing pancreatitis glucagon did not influence the significant fall in blood pressure elicited by the intraductal injection of trypsin or elastase or in the plasma calcium level in pancreatitis induced by trypsin or sunflower oil. Neither did glucagon affect the significant increase of plasma lipase activity in pancreatitis induced by trypsin or taurocholate. It also failed to reduce the 24-hour mortality rate and the extension of fat tissue necrosis in the abdominal cavity of pancreatitic animals. In contrast, glucagon treatment significantly reduced the amount of abdominal exudate associated with bile salt induced pancreatitis and, probably due to its pancreatic blood flow increasing effect, seemed to moderate the degree of tissue damage elicited in the pancreas by detergents such as taurocholate or lysolecithin.
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PMID:Glucagon treatment of experimental acute pancreatitis. 123 17

The effects of nutritional state, insulin, and glucagon on lipid mobilization were determined in rainbow trout, Oncorhynchus mykiss. In nutritional state experiments, fish were either fed continuously (except 24 to 36 hr prior to experimentation) with commercial trout chow or fasted for 4 weeks. Lipase activity in liver tissue isolated from fasted fish and cultured for 5 hr was greater than that in tissue isolated from fed fish and cultured. The presence of glucose (5.55 mM) in the incubation medium accentuates lipolytic activity in both liver and adipose tissue. Hormone response was assessed both in vivo and in vitro. Salmon insulin was injected into anesthetized fish (fed continuously except 24 hr prior to injections) in 10 microliters of saline/g body weight; final hormone dose was 100 ng/g body weight. Tissue and plasma were sampled 1 and 3 hr after injection. Insulin resulted in depressed plasma FA concentration and reduced hepatic triacylglycerol lipase activity. In vitro effects of hormones were evaluated by incubating liver and adipose tissue pieces in Hanks-MEM. Glucagon (bovine/porcine) directly stimulated lipid breakdown in both liver and adipose tissue. These actions were manifested by enhanced FA and glycerol released into the culture medium and by elevated triacylglycerol lipase activity. Insulin (bovine) generally appeared antilipolytic as this agent inhibited glucagon-stimulated lipase activity and glucagon-stimulated FA release. Furthermore, insulin (in the presence of glucose) reduced net lipolysis, as indicated by glycerol release, compared to control cultures. These results indicate that nutritional state and glucose are important modulators of lipid mobilization and that glucagon and insulin act directly on lipid storage sites to coordinate lipolysis in rainbow trout.
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PMID:Effects of nutritional state, insulin, and glucagon on lipid mobilization in rainbow trout, Oncorhynchus mykiss. 139 15

Lipoprotein lipase and hepatic lipase are members of the lipase gene family sharing a high degree of homology in their amino acid sequences and genomic organization. We have recently shown that isolated hepatocytes from neonatal rats express both enzyme activities. We show here that both enzymes are, however, differentially regulated. Our main findings are: (i) fasting induced an increase of the lipoprotein lipase activity but a decrease of the hepatic lipase activity in whole liver, being in both cases the vascular (heparin-releasable) compartment responsible for these variations. (ii) In isolated hepatocytes, secretion of lipoprotein lipase activity was increased by adrenaline, dexamethasone and glucagon but was not affected by epidermal growth factor, insulin or triiodothyronine. On the contrary, secretion of hepatic lipase activity was decreased by adrenaline but was not affected by other hormones. (iii) The effect of adrenaline on lipoprotein lipase activity appeared to involve beta-adrenergic receptors, but stimulation of both beta- and alpha 1-receptors seemed to be required for the effect of this hormone on hepatic lipase activity. And (iv), increased secretion of lipoprotein lipase activity was only observed after 3 h of incubation with adrenaline and was blocked by cycloheximide. On the contrary, decreased secretion of hepatic lipase activity was already significant after 90 min of incubation and was not blocked by cycloheximide. We suggest that not only synthesis of both enzymes, but also the posttranslational processing, are under separate control in the neonatal rat liver.
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PMID:Lipoprotein lipase and hepatic lipase activities are differentially regulated in isolated hepatocytes from neonatal rats. 156 12


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