大鼠心肌线粒体缺血再灌损伤及SOD抗缺血再灌损伤作用的形态计量研究

研究了在体大鼠心肌缺血再灌模型心肌线粒体再灌损伤和SOD抗缺血再灌损伤的作用。实验分为:A组(缺血再灌组)B组(SOD组)和C组(假手术组)。电镜见A组线粒体高度肿胀、外膜缺损、嵴断裂溶解,出现无定形致密体、四膜嵴和杆状嵴等改变。B组线粒体轻度或中度肿胀、少数有轻度嵴溶解。个别线粒体内出现无定形致密体。三组线粒体超微结构立体计量数据比较,A组线粒体密度、线粒体体密度与肌原纤维体密度比率增高((P<0.01),线粒体比表面和比膜面降低(P<0.01)。自身动图像分析仪检测SDH反应灰度值A组呈强损伤反应,B组反应较轻,二者差别有显著性(P<0.05)。结果表明,心肌缺血再灌可致线粒体发生不可逆性损伤,SOD能减轻线粒体缺血再灌性损伤。

A MORPHOMETRIC STUDY ON THE MYOCARDIAL MITOCHONDRIAL ISCHEMIA-REPERFUSION INJURY AND PROTECTIVE EFFECTS OF SOD AGAINST ISCHEMIA-REPERFUSION INJURY IN RAT

The myocardial mitochondrial ischemia-reperfusion injury and protective effects of SOD against ischemia-reperfusion injury with ischemia-reperfusion model of rat heart, were studied in vivo The expriment was divided randomly into three groups, i.e., ischemia (60min)-reperfusion (120min) group (group A), SOD-treated group (group B) and sham-opertion group (group C). Electron microscopic observation showed that the overwhelming majority of the mitochondria in group A occured irreversible injury, including serious swelling, clearing of the matrix, broken cristae amorphous dense bodies, rod-shaped cristae, tetramembrane cristae and mitochondrial membrane defects etc. In group B, slight or moderat swollen, decreasing density of the matrix, reducing of the density of cristae were observed in some of mitochondria. Occasionlly, the amorphous dense bodies were found in one or two mitochondria. Ultrastructure sterelolgical quantitative result revealed that the mitochondrial volume density (Vvmit) and the ration of Vvmit to myofilamental volume density were' in credsed in group A, but specific surface and specific membrane were decreased. In comparing with group B, these differences are statistically signficant (P<0.01). SDH is a mark enzyme of mi tochondrion. With an aid of IBAS image analysis system, serious injury reaction of SDH were showed in group A, slight reaction in group B. The difference is significant (P< 0.05). These results suggest that the SOD may be to protect the myocardial mitochondria against of ischemia-reperfuison damages.