【摘要】 为探讨兔左室肥厚心肌内膜下、中层及外膜下单个细胞跨膜动作电位 (AP)的不均一性改变。将实验兔分为手术组和假手术组。手术组行腹主动脉缩窄术制备心肌肥厚模型 ,假手术组仅分离暴露腹主动脉而不缩窄。按胶元酶二步消化法分离兔心室肌细胞 ,其中用剃须刀分离左室游离壁内、中、外三层心肌。采用全细胞膜片钳记录AP。结果 :手术组三层心肌细胞AP复极达 90 %的时程 (APD90 ) (内膜下 :181± 18ms,中层 :2 4 6± 2 1ms,外膜下 :196± 15ms)较假手术组均明显延长 (内膜下 :14 2± 13ms,中层 :182± 15ms,外膜下 :15 8± 16ms,n =13,P <0 .0 1～ 0 .0 5 ) ,且以中层心肌细胞延长比例最大。手术组早期后除极的发生率明显大于假手术组 (6 0 %vs 10 % ,n =10 ,P <0 .0 0 1)。结论 :兔左室肥厚三层心肌细胞间的跨室壁复极不均一性明显增大。更多还原

【Abstract】 To investigate the heterogeneous changes of the action potential of the cardiomyocytes sub-types in rabbits with left ventricle hypertrophy. Rabbit left ventricular hypertrophy was induced by partial ligation of the abdominal aorta. Myocytes were isolated by a two step enzymatical method. The sub-endocardial (Endo) and sub-epicardial (Epi) tissues were separated from other region (midmyocardium, M) with a razor. Patch clamp techniques were used to record the action potential. Results: The action potential duration(APD 90) in three layers were all significantly prolonged in hypertrophied cells(Endo:181±18ms,M:246±21ms,Epi:196±15ms)compared to control cells(Endo:142±13ms,M:182±15ms,Epi:158±16ms.n=13,P<0.01～0.05). And the prolongation was more pronounced in M cells than that in Epi or Endo cells. The incidence of EAD was higher in hypertrophied cells than in control cells (60% vs 10%,n=40,P<0.001).Conclusion: The transmural heterogeneity changes of action potentials increased significantly in the rabbit hypertrophied left ventricular.更多还原