Rapid Publications Stimulation of Adenylate Cyclase by Ca and Calmodulin in Rat Islets of Langerhans Explanation for the Glucose-induced Increase in Cyclic AMP Levels
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چکیده
The effect of Ca and calmodulin has been studied on adenylate cyclase activity in homogenates of rat islets of Langerhans. EGTA had a stimulatory effect on the enzyme in accord with the known inhibitory effect of Ca. In contrast, the addition of Ca together with calmodulin is stimulatory and demonstrates the existence of a Ca-dependent adenylate cyclase in islets of Langerhans. It is suggested that the glucoseinduced increase in cyclic AMP concentrations in intact islets is a secondary consequence of the glucose-induced increase in cytosol free-Ca concentrations which, with calmodulin, causes an increase in the activity of adenylate cyclase. DIABETES 29:74-77, January 1980.
منابع مشابه
Effects of dehydrouramil on protein phosphorylation and insulin secretion in rat islets of Langerhans.
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