BLOCKERS OF CA2+ CHANNELS IN THE PLASMALEMMA OF PERFUSED CHARACEAE CELLS

Ionic currents in the plasmalemma of perfused Nitella syncarpa cells i dentified as currents through Ca2+ channels were registered for the fi rst time. The effect of 1,4-dihydropyridine derivatives (nifedipine, n itrendipine, riodipine) and phenylalkylamines (verapamil, D600) as wel l as the agonist CGP-28392 on the Ca2+ channels in the plasmalemma of perfused cells of Nitellopsis obtusa and Nitella syncarpa have been st udied. A blocking effect of 1,4-dihydropyridine derivatives and phenyl alkylamines on the plasmalemma Ca2+ channels has been detected. Phenyl alkylamines have been found to block both inward and outward Ca2+ curr ents. The activating effect of the agonist CGP-28392 on the Ca2+ chann els of plasmalemma has been shown.