Effect of GBE50 on L-type calcium current and cytosolic[Ca~(2+)]_i in ischemic guinea pig ventricular myocytes / 中国药理学通报

ABSTRACT

Aim To observe the effect of Ginkgo biloba extract 50(GBE50)on L-type calcium current and cytosolic[Ca~(2+)]_i in ischemic guinea pig ventricular myocytes.Methods Single ventricular myocytes were isolated by enzymatic dissociation. I Ca-L was recorded by whole-cell patch clamp technique in voltage clamp mode.[Ca~(2+)]_i was detected by laser confocal micros-copy and represented by relative fluorescent intensity (FI).Results During ischemia, the peak Ca~(2+) current was reduced, and the I-U curve of I Ca-L was shifted upward.50 mg·L~(-1) GBE50 reversed the change induced by ischemia(n =6, P >0.05).After perfusing ischemic solution for 12 min, intracellular calcium concentration was increased(n =10, P <0.01).After perfusion with ischemic solution containing 50 mg·L~(-1) GBE50, the increase of intracellular calcium concentration was markedly inhibited(n =10, P >0.05).Conclusion GBE50 can reverse the decrease of I Ca-L and partially inhibit calcium overloading during ischemia.