[Effect of jiuxinfumai injection on L-type calcium currents in single guinea pig ventricular myocytes].

Objective: To determine the effect of 311 and 417, both active ingredients isolated from Jiuxinfumai injection (Citrus Aurantium) on L-type calcium currents (I(Ca-L)) in ventricular myocytes of guinea pigs.

Methods: Single myocytes were dissociated by enzymatic dissociation method. The whole-cell patch-clamp recording technique was used to record the change of calcium current after the administration of 311and 417.

Results: 311 (10, 25, 50, 100 mmol/L) increased the (I(Ca-L)) by 8.27%, 27.29%, 41.01%, and 48.74% (P < 0.05), respectively. 417 (10, 25, 50, 100 mmol/L) increased the (I(Ca-L)) by 10.05%, 30.12%, 43.05%, and 51.90% (P < 0.05), respectively. Both 311 and 417 changed the (I(Ca-L)) significantly in a concentration-dependent manner. They did not change the shape of I-V cruves.

Conclusion: 311 and 417 can increase I(I(Ca-L)) n ventricular myocytes of guinea pigs in a dose-response manner.