Effects of insulin and streptozotocin-diabetes on isoproterenol-stimulated cyclic AMP production in myocytes isolated from rat heart.
Isoproterenol (ISO), at concentrations of up to 10(-5) mol/L, caused a dose-dependent stimulation of cyclic AMP (cAMP) production in rat cardiomyocytes. At higher ISO concentrations, relative inhibition was seen. Insulin augmented ISO-stimulated cAMP production and appeared to mitigate the toxic effects of high ISO concentrations. This synergy between insulin and ISO observed in cardiomyocytes was not observed in adipocytes. Streptozotocin (STZ)-diabetes abolished the stimulatory effects of insulin on ISO-induced cAMP production in cardiomyocytes.
Almira
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Department of Medicine, University of Florida, Gainesville 32610.
Misbin
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RI
D000818:Animals; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D006321:Heart / Q000187:drug effects; D007328:Insulin / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology*; D007700:Kinetics; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D012016:Reference Values
D007328:Insulin; D000242:Cyclic AMP; D007545:Isoproterenol