论文部分内容阅读
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<0.05),with a significant change in the slope factor(k)(from 8.8 ± 0.8 to 11.1 ± 0.9,n=6,P<0.05).Didrovaltrate did not affect the activation curve.CONCLUSION:Didrovaltrate blocks I Ca-L in a concentration-dependent manner and probably inhibits I Ca-L in its inactive state,which may contribute to its cardiovascular effect.
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 = 8, P <0.01), respectively.Didrovaltrate shifted upwards the current-voltage curves of I Ca-L without changing their active, peak and reverse potentials. Dodrovaltrate 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 <0.05) with a significant change in the slope factor to 11.1 ± 0.9, n = 6, P <0.05) .Didrovaltrate did not affect the activation curve. CONCLUSION: Didrovaltrate blocks I Ca-L in a concentration-dependent manner and probably inhibits I Ca-L in its inactive state, which may contribute to its cardio vascular effect.