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我们采用蛋白酶（０．２ｍｇ／ｍｌ）循环消化的方法获取了７０％～８０％耐钙豚鼠心肌细胞，并用膜片钳全细胞式记录方法，初步观察了卡托普利（Ｃａｐｔ）对心室肌细胞跨膜电位及Ｌ型钙电流的影响。实验表明，Ｃａｐｔ１０μｍｏｌ／Ｌ显著缩短豚鼠心肌单细胞的动作电位时程（ＡＰＤ），药物作用１０分钟后，ＡＰＤ５０缩短３７．２２％，ＡＰＤ９０缩短３５．３３％（ｎ＝３，Ｐ＜０．０５）；但对静息电位（ＲＰ）、超射（ＯＳ）和动作电位幅度（ＡＰＡ）无显著影响。当心肌细胞的保持电压为－４０ｍＶ，除极到０ｍＶ，刺激电压时程为２５０ｍｓ，频率为０．５Ｈｚ时，Ｃａｐｔ１０μｍｏｌ／Ｌ可使Ｌ型钙内向峰电流减少４２．６８％，正常对照组在同一时间内仅下降４．１％（ｎ＝３，Ｐ＜０．０５）。可见，卡托普利具有类似维拉帕米样Ｌ－型钙通道阻断剂作用。
In this study, 70% -80% calcium-resistant guinea pig cardiomyocytes were obtained by cyclic digestion with protease (0.2 mg / ml). Cardiomyocytes were harvested by whole-cell recording with patch-clamp technique. Cell transmembrane potential and L-type calcium current. Experiments showed that Capt10μmol / L significantly shortened the action potential duration (APD) of guinea pig single-cell myocardium. After 10 minutes of drug treatment, APD50 shortened 37.22% and APD90 shortened 35.33% (n = 3, P <0.05) ), But no significant effect on resting potential (RP), supraoptic (OS) and action potential amplitude (APA). When the holding voltage of myocardial cells is -40mV, in addition to the extreme 0mV, stimulating voltage duration is 250ms, the frequency of 0.5Hz, Capt10μmol / L can L-type calcium inward peak current reduction of 42.68%, the normal control group Only decreased by 4.1% at the same time (n = 3, P <0.05). Can be seen captopril has a similar verapamil-like L-type calcium channel blocker effect.