Abstract
The direct actions of phencyclidine (PCP) on mammalian sarcolemma were examined by determination of the drug's effects on the action potentials of isolated guinea-pig ventricular cells, and on the underlying ionic currents. PCP (10-6 to 10-4 M) did not alter the resting membrane potential but produced a dose-dependent prolongation of the duration of the action potential, and a reduction of the rate of depolarization of phase 0 (V(max)) of the action potential. Voltage clamp experiments revealed that PCP blocks both myocardial Ca++ channels and myocardial time-dependent K+ channels. The K+ channel blockade was shown to exhibit an apparent voltage-dependence. The effects of PCP on these ionic channels could explain previous reports of it prolonging myocardial action potentials and conflicting reports of positive and negative inotropism.
Original language | English |
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Pages (from-to) | 131-136 |
Number of pages | 6 |
Journal | Journal of Pharmacology and Experimental Therapeutics |
Volume | 237 |
Issue number | 1 |
State | Published - 1986 |
ASJC Scopus subject areas
- Molecular Medicine
- Pharmacology