冷停搏液灌注途径对心肌酶功能和超微结构的影响

Effects of the Route of Cold Cardioplegia on Enzyme Function and Ultrastructures of the Myocardium.

根据冷停搏液不同的灌注途径，１８只犬等分成三组：组Ⅰ为主动脉灌注，组Ⅱ右房灌注，组Ⅲ主动脉灌注加冠状静脉窦堵塞。主动脉阻断１ｈ，同时阻断左前降支。结果表明，组Ⅰ梗阻的左前降支辖区心肌组织有氧代谢标志酶－琥珀酸脱氢酶（ＳＤＨ）活性明显降低，无氧糖酵解标志酶（ＬＤＨ）活性增强。心肌纤维和线粒体水肿明显。组Ⅱ和组ⅢＳＤＨ活性高，ＬＤＨ活性正常，心肌超微结构基本正常。由此表明，存在左前降支梗阻时，右房灌注和主动脉灌注加冠状静脉窦堵塞增加对缺血心肌超微结构和酶功能的保护。

Experimental observations were made in 18 dogs. According to different perfusion routes of cold cardioplegia adopted, the 18 dogs were equally divided into 3 groups: GroupⅠ received aortic perfusion,Group Ⅱright atrial perfusion, GroupⅢaortic perfusion combined with coronary sinus occlusion. The aorta and left anterior descending branch were clamped for one hour. The results indicated that the activities of succinate dehydrogenase (SDH) decreased significantly and these of lactic dehydrogenase(LDHI) increased in the occluded LAD region in GroupⅠ. Edema of myocardial fibers and mitochondria was obvious. On the contrary, SDH activity was higher and LDH activity was normal in GroupⅡ and GroupⅢ .The myocardial ultrastructures were found normal. It suggested that right atrial perfusion and aortic perfusion with coronary sinus occlusion increased the protective effect on ischemic myocardium .