Effect of isoproterenol on myocardial creatine kinase activity in rats.
Isoproterenol (0.1-500 mg/kg) decreased the myocardial creatine kinase (CK) activity in rats. The maximum effect was already reached with 10 mg/kg, decreasing the enzyme activity to 58.5% of the control values. The beta-blocking agents propranolol and practolol, and also glucocorticosteroids inhibited the isoproterenol effect. The relative CK isoenzyme composition of the myocardium was not grossly altered by isoproterenol, as shown by DEAE-Sephadex A-50 macrocolumn chromatography. --Serum CK was increased significantly after the administration of the excessive dose of 500 mg isoproterenol/kg.
D000818:Animals; D003402:Creatine Kinase / Q000037:antagonists & inhibitors* / Q000097:blood; D004347:Drug Interactions; D005938:Glucocorticoids / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D009206:Myocardium / Q000201:enzymology*; D011217:Practolol / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D013997:Time Factors
D005938:Glucocorticoids; D007527:Isoenzymes; D011433:Propranolol; D003402:Creatine Kinase; D007545:Isoproterenol; D011217:Practolol