论文部分内容阅读
目的观察牛磺酸(TaurineT)对甲状腺机能亢进(以下简称甲亢)豚鼠离体心室肌细胞动作电位的影响,探讨牛磺酸对甲亢豚鼠心室肌细胞电活动的影响及其机制。方法采用微电极技术,引导心室肌细胞动作电位,观察在甲亢状态下牛磺酸对心室肌细胞动作电位各参数的影响。结果 ( 1 )甲亢组豚鼠心室肌细胞动作电位时程 (APD20, APD50,APD90, APD)及有效不应期(ERP)显著缩短,甲亢豚鼠心室肌细胞动作电位幅度 (APA),零期最大除极速率 (Vmax)无显著性变化; (2)加入牛磺酸后,甲亢豚鼠心室肌细胞动作电位时程APD50, APD90, APD显著延长,而APD20及动作电位幅度(APA)无显著变化 ,零期最大除极速率(Vmax)显著降低,ERP显著延长; (3)给甲状腺功能正常组加入牛磺酸后,豚鼠心室肌细胞动作电位时程APD20, APD50, APD90显著缩短,APD亦有缩短,但无显著性差别,ERP显著延长,APA无显著性变化,Vmax显著性降低。结论 (1)较高浓度的牛磺酸可能对甲亢豚鼠的离体心室肌细胞膜的外向(主要是K+ )电流具有一定的抑制作用; (2)对甲状腺功能正常豚鼠的心室肌细胞,一定程度上,可能促进钾外流; (3)无论是正常组还是甲亢组,在加入牛磺酸后,Vmax均出现显著降低,提示较高浓度的牛磺酸对心室肌细胞的INa也有影响。
Objective To observe the effect of taurine on the action potential of isolated ventricular myocytes in guinea pigs with hyperthyroidism (Hyperthyroidism) and to investigate the effect and mechanism of taurine on the electrical activity of ventricular myocytes in hyperthyroid guinea pigs. Methods The microelectrode technique was used to guide the action potential of ventricular myocytes. The effects of taurine on the parameters of action potential of ventricular myocytes in hyperthyroidism were observed. Results (1) The action potential duration (APD20, APD50, APD90, APD) and effective refractory period (ERP) of ventricular myocytes of hyperthyroidism group were significantly shortened, the amplitude of action potential (APA) (2) After adding taurine, the APD50, APD90 and APD of ventricular myocytes in hyperthyroid guinea pigs were significantly prolonged, while there was no significant change in APD20 and action potential amplitude (APA) (3) After adding taurine to the normal thyroid function group, APD20, APD50 and APD90 in the action potential duration of guinea pig ventricular myocytes significantly shortened and APD also shortened, But no significant difference, ERP significantly prolonged, APA no significant change, Vmax significantly reduced. Conclusions (1) The higher concentration of taurine may inhibit the outward (mainly K +) currents of isolated ventricular myocytes in hyperthyroid guinea pigs. (2) The inhibitory effect of taurine on ventricular myocytes in guinea pigs with hyperthyroidism, to a certain extent , Which may promote the outflow of potassium. (3) The Vmax decreased significantly after adding taurine in both normal and hyperthyroid groups, suggesting that higher concentrations of taurine have an effect on INa of ventricular myocytes.