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)

In dogs with acute experimental pancreatitis (AEP) induced according to Elliotts method the total, free and latent activity of lysosomal hydrolases (acid phosphatase, beta-glucuronidase and cathepsins) in whole homogenates and some subfractions of pancreas were studied. The animals were divided into three groups of 6 dogs each: I. control healthy dogs. II. AEP-treated with glucagon (0.33 mg of glucagon in drop infusion 3 times every six hours). III. AEP without any drug treatment. In dogs treated with glucagon the significant decrease of relative free activity of all tested hydrolases (66-80%) in comparison with the group without any treatment (III/80-90%) was found. Moreover significant decrease of total catheptic activity (about 1/3) in the former group was demonstrated. Incubation of lysosomal enriched fraction taken from group II/in medium buffered to pH 5.0 caused decreasing release of catheptic activity (60% of total) in comparison with the group III (75%). The histochemical reaction for acid phosphatase according to Gomoris method in pancreatic acinar cells of dogs treated with glucagon was less intensive than reaction in untreated animals. These results indicate on the less impairment of pancreatic lysosomes in AEP treated with glucagon in comparison with that in untreated animals.
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PMID:The lysosomal hydrolases in acute experimental pancreatitis in dogs treated with glucagon. 84 47

Hepatocyte lysosomes disassemble materials derived from intracellular sources, including lipid-containing membranes, by a process called autophagy. In addition, hepatocyte lysosomes can release their contents into bile by exocytosis. Therefore, using both in vivo and in vitro models, we tested the hypothesis that acute pharmacologic induction of autophagy would modify the biliary excretion of lysosomal protein and of lipids. We treated rats with a single dose of chloroquine (10 mg/kg), glucagon (1 mg/kg), or control solutions and collected bile via bile fistulas. Both chloroquine and glucagon immediately caused a marked and parallel decrease in biliary excretion of three lysosomal enzymes, N-acetyl-beta-glucosaminidase, beta-glucuronidase, and beta-galactosidase, to 25%-30% of baseline values (p less than 0.01). This decrease was sustained for 2 h after glucagon and 4 h after chloroquine administration. In contrast, biliary lipid changes were minor: a slight lowering of biliary cholesterol secretion after chloroquine (p less than 0.05), but no change in biliary bile acids, cholesterol, and phospholipid secretion after glucagon. Changes in biliary excretion of lysosomal enzymes accompanying chloroquine and glucagon administration were associated with morphologic evidence of autophagy as assessed by electron microscopy and by increased fragility of hepatic lysosomes as assessed by latency of N-acetyl-beta-glucosaminidase. These in vivo changes in biliary lysosomal enzyme excretion induced by chloroquine and glucagon were confirmed in vitro using the isolated perfused rat liver. Thus, acute induction of autophagy results in conservation of hepatic lysosomal protein and has virtually no effect on biliary lipid excretion.
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PMID:Pharmacologic perturbation of rat liver lysosomes: effects on release of lysosomal enzymes and of lipids into bile. 313 15

Isolated rats livers were perfused with Krebs-Ringer-Bicarbonate (KRB) and different doses of insulin or glucagon and with insulin plus glucagon. The isolated liver of fasted rats and of rats treated with streptozotocin were perfused with (KRB). The glomerulopressin activity of the ultrafiltrate of the liver perfusates were assayed in the tonic tension contraction (TTC) of isolated stomach fundus from rats. As glomerulopressin is known to be a glucuronide, it was inactivated with beta-glucuronidase to confirm that the effect on the stomach fundus was due to the glomerulopressin and not to an autacoid. It was observed that glucagon increased the glomerulopressin activity of the perfusate and that this activity was independent of the dose of glucagon used. Insulin produced a decrease in the glomerulopressin activity of the perfusate, there being a log-dose relationship between insulin and glomerulopressin. There is a dose of insulin (1,5 X 10(-5) U/min/kg) that potentiates the response to glucagon. Fasting and treatment with streptozotocin induced an increase in the glomerulopressin activity of the perfusate. These results suggest that glomerulopressin production is influenced by glucagon and insulin, and that there is a specific ratio between these hormones that is very effective in the production of glomerulopressin.
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PMID:Influence of insulin and glucagon on the production of glomerulopressin by isolated rat liver. 675 88

This study was done to determine glucagon's effect on protein biliary excretion in anesthetized, bile duct-cannulated guinea pigs. Glucagon (1.4 nmol.min-1.kg-1) induced choleresis and increased protein biliary concentration from 0.12 +/- 0.04 to 0.20 +/- 0.6 mg/ml and protein output from 22.8 +/- 3.8 to 54.5 +/- 16.1 micrograms.kg-1.min-1. Protein biliary excretion increased during the first 10 min of glucagon infusion and progressively declined thereafter. Biochemical analysis of biliary protein revealed that the increase could be accounted for primarily by an increase in the lysosomal enzymes acid phosphatase and beta-glucuronidase. Biliary excretion of the canalicular membrane enzymes 5'-nucleotidase and alkaline phosphatase only modestly increased, whereas that of [14C]sucrose, a marker of paracellular fluid transport, was unaffected. On the other hand, glucagon enhanced biliary entry of horseradish peroxidase in a fashion similar to that observed with total endogenous protein. These effects were mediated by the adenosine 3',5'-cyclic monophosphate (cAMP) system, since infusion of dibutyryl-cAMP at 0.5 mumol.kg-1.min-1 increased bile flow and biliary protein excretion in a time-dependent manner, as observed with glucagon. Glucagon's failure to sustain enhanced protein biliary output was not due to declining hepatic concentrations of cAMP or to depletion of hepatocellular lysosomal enzymes. These studies provide evidence that glucagon stimulates biliary excretion of protein in guinea pigs that can be accounted for by biliary discharge of enzyme originating from the canalicular membrane and, primarily, from the lysosomal compartment. Although the precise mechanism(s) underlying these effects remains to be elucidated, it is suggested that the increase in canalicular membrane enzyme excretion is due to glucagon's effect on exocytosis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Glucagon induces biliary protein excretion in guinea pigs. 838 43