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目的 观察异丙酚对心肌细胞钙离子移动和Ｌ－型钙通道电流（Ｉｃａｌ）的影响。方法 急性分离的大鼠单个心室肌细胞，采用Ｆｌｕｏ－３ＡＭ 钙荧光指示剂和膜片钳技术，观察５０μｍ ｏｌ·Ｌ－ １ 或２５０μｍ ｏｌ·Ｌ－ １异丙酚对高浓度ＫＣｌ或咖啡因所诱发细胞内钙离子浓度的变化，以及对Ｌ－型钙通道电流的影响。结果 ５０μｍ ｏｌ·Ｌ－ １或２５０μｍ ｏｌ·Ｌ－ １ 异丙酚明显减弱ＫＣｌ所诱发细胞内钙离子的增加，浓度越高其减弱作用越明显；而对咖啡因所致胞浆内钙离子的增加无明显影响。使钙通道电流峰值分别较用药前下降２４．８％ 和４９．６％ （Ｐ＜ ０．０５，ｎ＝ ５）。洗去异丙酚后Ｉｃａ 可基本恢复至基础水平。结论 异丙酚的负性肌力作用至少部分是由于其影响心肌细胞胞膜功能，减少钙离子跨膜内流以及抑制细胞膜缓慢内流的Ｌ－钙通道电流所致，而对肌浆网功能似乎无明显作用。
Objective To investigate the effect of propofol on calcium ion mobility and L-type calcium channel current (Ical) in cardiomyocytes. Methods Single ventricular myocytes were isolated from acute ventricular myocytes. Fluo-3AM calcium fluorescence indicator and patch-clamp technique were used to observe the effect of 50μmol·L-1 or 250μmol·L-1 propofol on high concentration KCl or caffeine Induced changes in intracellular calcium concentration, and the effects on L-type calcium channel currents. Results 50μmol·L-1 or 250μmol·L-1 propofol obviously decreased the increase of intracellular Ca2 + induced by KCl, while the higher the concentration of propofol, the more obvious the effect was. However, Ca2 + Increase no significant effect. Calcium channel current peak value decreased by 24.8% and 49.6% (P <0.05, n = 5) compared with before treatment. Ica after washing to remove propofol can be basically restored to the basic level. Conclusions The negative inotropic effect of propofol is due at least in part to its effect on myocardial cell membrane function, reduction of calcium ion transmembrane influx, and inhibition of slow influx of L-calcium current in the cell membrane, Seems no obvious effect.