摘要
目的 :观察缺血预处理 (IPC)对体外循环中心肌组织磷脂酶A2 (PLA2 )活性和细胞膜微黏度变化的影响 ,评价IPC的心肌保护作用。 方法 :将 72只健康家猫随机均分为 3组 :单纯体外循环组、缺血再灌注组和IPC组。在猫体外循环模型的基础上 ,测定各组猫心肌丙二醛含量和血清乳酸脱氢酶水平 ,并应用荧光偏振法测定心肌细胞膜的微黏度 ,同时测定心肌组织PLA2 活性。比较IPC组和缺血再灌注组体外循环中心肌细胞膜微黏度和心肌组织PLA2 活性的变化。 结果 :IPC可明显降低体外循环中的血清乳酸脱氢酶浓度、心肌丙二醛含量、心肌细胞膜微黏度和心肌组织PLA2活性。结论 :IPC可通过抑制心肌组织PLA2 活性以维持心肌细胞膜流动性 ,从而发挥其良好的心肌保护作用。
Objective: To elucidate the effect of ischemic preconditioning(IP C )on activity of phospholipase A 2(PLA 2)and mic roviscosity of myocardial cell membrane during cardiopulmonary bypass ( CPB). Methods: Seventy two felines were randomized into there groups: groupⅠ(n=2 4),in which CPB was conducted without aortic cross clamping (ACC); group Ⅱ(n=2 4),with 60 min ACC followed by 90 min reperfusion, and cardiople gia used during period of ACC; group Ⅲ(n=24), wi th protocol similar to that of group Ⅱ except for three round 15 min IPC applied before ACC. Serum lactate dehydrogenase (LDH)level and malondialdehyde (MDA)content of myocardium were assayed before and at the end of CPB. Microviscosity of myoc a rdial membrane was evaluated 45, 75, 105, 120 and 135 min after beg inning of CPB using fluorescence polarization technique, and the activity of PLA 2 of myoc ardium was measured simultaneously. Results: Both serum LDH level and MDA content of myocardium were significan tly i ncreased at the end of CPB in group Ⅱ, which can be markedly downregulated by I PC in group Ⅲ. In addition, the increased microviscosity of myocardial cell m em brane was found during both ischemia and reperfusion periods in group Ⅱ, accomp anied by elevation of the PLA 2 activity of myocardium, and IPC significan tly d ecreased microviscosity of myocardial cell membrane as well as the PLA 2 act ivity of myocardium during CPB in group Ⅲ. Conclusions: IPC can protect myocardial cells from ischemia and reperfusio n inju ry by maintaining the fluidity of myocardial membrane during CPB, which may be due to the inhibitory of activity of PLA 2.
出处
《中国循环杂志》
CSCD
北大核心
2003年第5期385-387,共3页
Chinese Circulation Journal
基金
上海市科技启明星计划资助项目 ( 0 0QB1 40 53)
上海市曙光计划资助项目 ( 0 2SG30 )
