The beta-adrenergic regulation of the Na, K-ATPase activity in the sarcolemma of the heart muscle

• Published in: Nauchnye doklady vysshei shkoly. Biologicheskie nauki no. 6; p. 138
• Main Authors: Osadchaia, L M, Mugula, Zh, Stefanov, V E
• Format: Journal Article
• Language: Russian
• Published: Russia (Federation) 1990
• Subjects: Animals; Ca(2+) Mg(2+)-ATPase - metabolism; Calcium-Transporting ATPases - metabolism; Dose-Response Relationship, Drug; Heart - drug effects; In Vitro Techniques; Isoproterenol - pharmacology; Male; Myocarditis - chemically induced; Myocarditis - enzymology; Myocardium - enzymology; Propranolol - pharmacology; Rats; Receptors, Adrenergic, beta - drug effects; Receptors, Adrenergic, beta - physiology; Sarcolemma - drug effects; Sarcolemma - enzymology; Sodium-Potassium-Exchanging ATPase - analysis; Sodium-Potassium-Exchanging ATPase - metabolism
• ISSN: 0470-4606

Using a sensitive potentiometric method the effect of isoproterenol upon the activity of Na, K-ATPase in cardiomyocytes has been studied. The activity of the enzyme in rat sarcolemma at isoproterenol-induced myocarditis decreases by 42%. A direct action of isoproterenol on the Na, K-ATPase activity in sarcolemma in vitro has been investigated. In the concentration range 10(-9)-10(-3) M (from receptor-binding up to cardiotoxic) a gradual decrease of the activity reaching the complete inhibition at 10(-3) M is revealed. Antagonist of beta-adrenoreceptors propranolol in concentrations required for displacing the agonist (10(-9) M) provides for the recovery of the Na, K-ATPase activity up to 76% of its normal activity. This action transforms into nonspecific inhibition at rising concentration of the antagonist. Possible mechanisms of the beta-adrenergic regulation effect in cardiomyocytes on Na, K-ATPase of the sarcolemma are discussed.