采用双微电极电压钳制术研究3，6－（二甲氨基）-二苯骈碘杂环依地酸盐（IHC-72）对家兔浦肯野纤维慢钙通道的影响。当维持电位为-40mV，刺激频率为0．2Hz，钳制时间为500ms，除极到15mV时，101．6μmol/LIHC-72对慢内向电流（Isi）的抑制效应在5、10、15、20、25min时分别为（％）：20．5、41、51.8、59．8和60．1（P皆＜0．01），但灌流20min与25min时效应无明显差别，冲洗20min不能完全洗脱。结果表明：IHC-72在20min内对Isi的抑制呈时间依赖性，且是通过细胞膜内侧的慢钙通道位点而起作用。 Double microelectrode voltage clamp technique was used to study the effects of 3,6- (dimethylamino) -benzodiazepine iodide-based edetate salt (IHC-72) on Purkinje fibers in rabbits. The inhibitory effect of 101.6μmol / LIHC-72 on the slow inward current (Isi) at the holding potential of -40mV, the stimulation frequency of 0.2Hz, the clamping time of 500ms and the depolarization of 15mV were in the range of 5, 10, 15, (%): 20.5,41,51.8,59.8 and 60.1 at 25min (all P <0.01), but there was no significant difference between the perfusion at 20min and 25min . The results showed that IHC-72 inhibits Isi in a time-dependent manner within 20 min and acts through a slow calcium channel site inside the cell membrane.