牛磺酸镁对哇巴因致大鼠心肌细胞心律失常模型钙离子通道的影响

目的:观察牛磺酸镁配合物(taurine magnesium coordination compound,TMCC)对哇巴因诱发心律失常大鼠心肌细胞L型钙电流(ICa-L)的影响。方法:酶解法分离大鼠单个心室肌细胞,采用全细胞膜片钳技术记录不同浓度TMCC及胺碘酮对正常细胞和哇巴因所致大鼠单个心室肌细胞心律失常模型ICa-L变化。结果:400μmol·L-1 TMCC显著增加大鼠正常心肌细胞ICa-L,胺碘酮则使之减小。5μmol·L-1哇巴因使ICa-L电流密度由(4.31±0.62)pA/pF减小到(2.90±0.35)pA/pF(n=5,P<0.01)。200和400μmol·L-1TMCC能显著恢复造模后的ICa-L。24.24μmol·L-1胺碘酮则使ICa-L减少到(2.55±0.20)pA/pF(n=5,P>0.05)。结论:400μmol·L-1 TMCC能显著增加正常细胞的ICa-L,对钙内流有促进作用,并可显著增加哇巴因诱导的心律失常大鼠心肌细胞异常减小的电流。

Effect of taurine-magnesium coordination compound on calcium channel in rat cardiomyocytes of arrhythmia induced by ouabain

Objective: To investigate the antiarrhythmic mechanism of taurine-magnesium coordination compound(TMCC) on L-type calcium current(ICa-L) in rat ventricular myocytes of arrhythmia induced by oubain.Methods: Enzymatic dissociation was used to get single rat ventricular myocytes.Whole-cell patch clamp was used to record ICa-L in normal cardiomyocytes and single rat ventricular cardiomyocytes of arrhythmia induced by ouabain.Results: In rat ventricular cardiomyocytes,ICa,L was increased by TMCC(400 μmol·L-1),while decreased by amiodarone.ICa-L was decreased from(4.31±0.62)pA/pF to(2.90±0.35)pA/pF(n=5,P<0.01)by 5 μmol·L-1 ouabain.TMCC(200,400 μmol·L-1) restored ICa-L significantly in rat ventricular myocytes of arrhythmia induced by oubain.Amiodarone decreased it to(2.55±0.20) pA/pF.Conclusion: TMCC(400 μmol·L-1) can increase ICa-L in normal cardiomyocytes and it also significantly increases ICa-L in single rat ventricular cardiomyocytes of arrhythmia induced by ouabain.