Tetrodotoxin slightly shortens action potential duration in ventricular but not in atrial heart muscle
- 1 January 1988
- journal article
- research article
- Published by Springer Nature in Cellular and Molecular Life Sciences
- Vol. 44 (1) , 16-17
- https://doi.org/10.1007/bf01960226
Abstract
Tetrodotoxin (TTX), at concentrations significantly decreasing maximal upstroke velocity (dV/dtmax) of the action potential, exerted variable effects on action potential duration (APD) in different myocardial preparations. APD was virtually unchanged by tetrodotoxin in the guinea pig atrium, but slightly shortened in the guinea pig ventricle at maximally effective concentrations. In the human ventricle, both dV/dtmax and APD were reduced in the same concentration range of TTX. These results suggest that a TTX-sensitive sodium current significantly contributes to the repolarization phase of the action potential in ventricular but not in atrial heart muscle.This publication has 19 references indexed in Scilit:
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