四种心肌保护方法对心肌细胞质膜蛋白的影响

目的：研究４种心肌保护方法对心细胞质膜蛋白结构和功能的影响。评价其心肌保护效果。方法复动物模型，检测心肌细胞质膜ＡＴＰ酶活笥、质膜蛋白形态，，二级结构及电泳谱型变化。结果：（１）因期间，各级一ａ＾＋，Ｋ＾＋泵活性均显著下降，体外循环１８０ｍｉｎ，Ⅵ组恢复较好，Ｃａ＾２＿，Ｍｇ＾２＋泵与Ｎａ＾Ｋ，Ｋ＾＋泵活必绫心。（２）复灌后１．８万以上质膜蛋白条下降；体外循环１８０ｍｉｎ，Ⅵ组恢复较好。Ｃａ＾２＋

Effects of 4 kinds of myocardial protection methods on the myocardial membrane-proteins

Objective: To investigate the effects of 4 kinds of myocardial protection methods on the myocardial membrane-proteins (MMPs), and to evaluate their cardioprotective effects. Methods: The feline cardiopulmonary bypass (CPB) models were established, and the activities of myocardial membrane ATPase, the alterations of MMPs electrophoretogram, the morphology and the secondary structures of MMPs were all detected. Results: (1) During aortic cross-clamping (ACC) period, the activities of myocardial membrane Na~+,K~+-ATPase were decreased significantly. After180 min CPB, better recovery were seen in Group M. The changes of myocardial membrane Ca~(2+),Mg~(2+)-ATPase activities were similar to that of Na~+, K~+-ATPase activities. (2) Deletions of MMPs, molecular mass less than 18 000, were observed to different extent after reperfusion. (3) No significant differences were detected in the equivalent diameters of MMPs particles in all groups. During ACC, the numbers of MMPs particles kept stable in Group W. (4) No relationships were established between the alterations of MMPs' secondary structures and myocardial ischemia/reperfusion injuries (IRI) in all groups. Conclusion: CPB without ACC exerts no detrimental effects on the MMPs. The activated proteinases may play an important role in the course of IRI. Four kinds of myocardial protection methods used in this study can not prevent the occurrence of IRI completely. Administration of warm blood cardioplegia continuously offers the best cardioprotection.