牛磺酸对大鼠心肌肌浆网钙转运功能的影响

EFFECTS OF TAURINE ON Ca^(2+) TRANSPORT OF RAT CARDIAC SARCOPLASMIC RETICULUM

目的：观察牛磺酸对大鼠心肌肌浆网（SR）钙转运的影响。方法：动物分为假手术、休克和牛磺酸组；盲肠结扎穿孔法复制休克模型；蔗糖密度梯度离心法制备心肌SR，分别测定SR钙摄取、[3H]ryanodine受体结合。结果：与休克组比较，牛磷酸组的SR摄钙率和最大援钙量分别提高91．5％（P＜0.01）和32．2％（P＜0．01），[3H]ryanodine受体结合Bmax值增加54.2％（P＜0．01），Kd值无明显变化。0．25～5mmol／L牛磺酸对正常大鼠钙转运无直接影响。结论：牛磷酸可以显著改善败血症休克大鼠心肌SR钙转运功能；其效应可能不是通过直接作用于SR所致。

To observe the effects of taurine on Ca2+ transport by cardiac sarcoplasmic reticulum (SR) in rats. Methods: Animals were divided into three groups of sham, shock and taurine administration; Rat septic shock model was produced by cecal ligation and puncture1 Cardiac SR membranesisolated by discontinuous sucrose centrifugation were used for assays of Ca2+ uptake and [3H]ryanodinereceptor binding. Results: Compared with shock group, the rate and the maximal capacity of SR Ca2+uptake increased by 91. 5% (Pw＜0. 01) and 32. 3% (P＜0. 01), while the Bmax value of [3H]ryanodinebinding to cardiac SR enhanced by 54. 2 % (P＜0. 01) with no changes in the Kd value in taurine administrated rats. Taurine 0. 25～5 mmol/L added to incubation fluid failed to increase the Ca2+ uptake and[3H]ryanodine binding to the SR isolated from control rats. Conclusion: Pretreatment with taurine significantly improved Ca2+transport function of cardiac SR of septic rats, the effects of taurine may not bethrough the direct influence on cardiac SR.