小鼠病毒性心肌炎与细胞凋亡及氧自由基的关系

The Relationship of Viral Myocarditis,Apoptosis and Oxygen Free Radical

采用电镜技术及原位末端标记法 ( TUNEL )对柯萨奇病毒 B3( CVB3)心肌炎小鼠不同时期心肌组织中细胞凋亡进行检测 ,并采用硫代巴比妥酸法检测外周血丙二醛 ( MDA)。CVB3感染 10 0只雄性 Balb/ c小鼠 ,VMC发病率为 86%。各期病鼠心肌中均见到凋亡细胞 ,包括心肌细胞、血管内皮细胞及间质细胞。 TUNEL法检出率为 78.94 % ,中、重度 VMC小鼠中阳性检出率明显高于轻度 VMC小鼠 ( P<0 .0 5)。感染后 7～ 14天心肌细胞凋亡百分率明显高于 2 1～ 2 8天 ( P<0 .0 5)。正常对照组未见凋亡细胞。感染后 7天始 MDA明显升高 ,14～ 2 1天为高峰 ,第 2 8天开始恢复。中、重度 VMC小鼠 MDA升高发生率明显高于轻度 VMC小鼠 ( P<0 .0 5)。实验组小鼠心肌细胞凋亡百分率与 MDA的变化趋势基本相同。说明细胞凋亡可能为 VMC中造成心肌损伤的重要发病机制之一 ,氧自由基 ( OFR)可能为 VMC细胞凋亡的促发因素之一。

Electronic microscopic and terminal trans ferasemediated dUPT biotin nick end labeling(TUNEL)assays quantified apoptosis in myocardium Malon dialdehyde(MDA)in serum were detected One hundred Balb/c mice were inoculated with CVB 3 The incidence of VMC was 86% Apoptotic cells detected in myocardium from CVB 3 injected mice included myocytes,endothelial cells and infiltrating cells in myocardium TUNEL positive myocytes increased significantly from 7 to 14 days p i then reduced from 21 to 28 days p i(P<0 05) The positive rate of TUNEL positive mice were more higher in mice exhibited moderate to severeer histopathology than that in mice exhibited mild histopathology(P<0 05) In experimental group,the level of MDA rised up significantly from 7 days p i and reached its peak at 14 days p i ,recovered from 28 days p i The level of MDA in serum from CVB 3 injected mice correlated with the degree of myocardial lesions significantly(P<0 05) Both of Apoptosis and MDA which can induce apoptosis significantly during 7 to 14 days p i It demonstrates that apoptosis might play an important role in the development of VMC Oxygen free radicals might be one of proapoptosis factors