[Strophanthin induced changes in the ion currents of Lymnaea stagnalis and Planorbis corneus neurons]

Experiments on isolated neurons of Lymnaea stagnalis and Planorbis corneus using the intracellular dialysis and fixed membrane potential techniques showed that strophanthin G in a concentration range from 10(-11) to 10(-6) M produce dolse-dependent reversible suppression of the ion currents in potassium, calcium, and sodium channels. At the maximum concentration (10(-6) M), the maximum suppression (up to 55% of that in the control) was observed for the calcium ion current. At the minimum concentration (10(-12) M), the drug did not influence the sodium ion current, but slightly (approximately by 5%) increased the calcium and potassium ion currents. In addition, strophanthin accelerated the inactivation of slow potassium ion currents.