异丙基肾上腺素导致的心肌肥厚大鼠心肌牛磺酸转运障碍

Taurine transport dysfunction in isoproterenol-induced rat myocardial hypertrophy

目的 观察异丙基肾上腺素 (isoproterenol,Iso)导致的心肌肥大大鼠的心肌细胞牛磺酸 (taurine ,TAU)跨膜转运功能的改变。方法 Iso诱导大鼠心肌肥厚 ;氨基酸分析仪测牛磺酸含量 ;用3H标记的牛磺酸测定心肌牛磺酸转运及牛磺酸与心肌浆膜结合功能。结果 Iso组动物较对照组的血浆和组织牛磺酸含量分别升高 49% (P <0 0 1)和降低35 % (P <0 0 1) ,心肌3H 牛磺酸摄入减少。 5min时释放量与总摄入百分比高于对照组 6 0 % (P <0 0 1) ,Iso组释放量增加。Iso心肌浆膜3H 牛磺酸结合量较对照组低 ,最大结合速率 (Bmax)较对照组低 45 % (P <0 0 5 ) ,治疗组较Iso组Bmax值增加 116 % (P <0 0 1) ,Kd值无明显差异。结论 Iso诱导的心肌损伤存在牛磺酸转运障碍 。

AIM To observe myocardial taurine transport in the isoproterenol(Iso) induced rats. METHODS Taurine content was determined with a amino acid analyser. Myocardial 3H taurine uptake and release, sarcolemma 3H taurine bound were determined by 3H taurine incubation. RESULTS Compared with control, the plasma and myocardium taurine concent increased by 49%(P<0 01) and decreased by 35% (P<0 01), respectively. The uptake of myocardial 3H taurine reduced, whereas H taurine release increased. The maximal bound velocity(B max ) was deceased by 45% (P<0 05). There were no significant changes in the K d value. CONCLUSION There is the impediment of taurine transport in the Iso induced myocardial hypertrophy, that exogenous taurine can efficiently prevent myocardial injury.