[Effect of antibodies specific to sarcolemma of cardiomyocytes in activity of 5-nucleotidase in rats].

Rabbit antibodies specific to sarcolemma of cardiomyocytes have been studied for their effect on activity of 5'-nucleotidase ecto-enzyme of the Wistar rat cardiomyocytes. It is shown that incubation of isolated plasma membranes of cardiomyocytes of rats (100 micrograms of protein) with the gamma-globulin fraction of antisarcolemmal cardial serum (gamma-ASCS, 20 micrograms protein) and with the gamma-globulin fraction of normal rabbit serum (gamma-NRS, 0.20 micrograms protein) promotes a decrease of the enzyme activity. An inhibiting effect was greatly pronounced in incubation with gamma-NRS and did not depend on the dose of antibodies and duration of their action. An assumption is made that inhibiting action of antibodies on activity of ecto-5'-nucleotidase may change adenosine concentration and may be one of elements in the mechanism promoting an increase of the intracellular calcium concentration.