OBJECTIVE:To investigate the effect of didrovaltrate on L-type calcium current(I Ca-L) in rabbit ventricular myocytes.METHODS:We used the whole cell patch clamp recording technique.RESULTS:Didrovaltrate at concentrations of 30 μg/L and 100 μg/L significantly decreased peak I Ca-L(I Ca-Lmax) from(6.01±0.48) pA/pF to(3.45±0.27) pA/pF and(2.16 ± 0.19) pA/pF(42.6% and 64.1%,n=8,P< 0.01),respectively.Didrovaltrate shifted upwards the current-voltage curves of I Ca-L without changing their active,peak and reverse potentials.Didrovaltrate affected the steady-state inactivation of I Ca-L.The half activation potential(V 1/2) was significantly shifted from(-26 ± 2) to(-36 ± 3) mV(n=6,P