E-C coupling during poisoning with 2,4-dinitrophenol and recovery in papillary muscle of guinea-pig: 2. Effect on the cardiac electrical activity.

-DNP (1 x 10(-4)M) reduced membrane resting potential, overshoot, rate of depolarization, conduction velocity, action potential plateau, twitch tension and increased the passive base tension. -All the electrical and mechanical effects were reversed by the wash out. -The results are consistent with an inhibition of the ion active transport by the membrane Na+-K+ pump and the SR Ca++ pump.