烧伤延迟复苏时大鼠心肌细胞线粒体呼吸功能的变化

目的:观察严重烧伤延迟复苏时大鼠心肌细胞线粒体呼吸功能的变化。方法:88只大鼠随机分为正常对照组(A组)、即时复苏组(B组)和延迟复苏组(C组),B组和C组造成20％总体表面积Ⅲ度烧伤,并测定伤后1h,3h,6h,24h,48h线粒体呼吸Ⅲ、Ⅳ态及呼吸控制率(RCR);测定线粒体呼吸链NADH-CoQ还原酶、琥珀酸脱氢酶活力。结果:①烧伤后B、C组心肌细胞线粒体RCR和NADH-CoQ还原酶显著低于A组(P<0．05);C组显著低于B组(P<0．05);②B组心肌细胞线粒体RCR和NADH-CoQ还原酶活力复苏3小时代偿性增高,但后期进一步降低;③伤后3小时内,B、C组心肌细胞线粒体内琥珀酸脱氢酶活力无显著降低(P >0．05);复苏后期显著低于A组(P<0．05),C组显著低于B组(P<0．05)。结论:严重烧伤大鼠延迟复苏时会加重心肌细胞线粒体呼吸功能损伤。

Changes of mitochondria function of myocardial cell in burnt rats after delayed fluid resuscitation

Objective: To investigate the changes of mitochondria respiratory function of myocardial cell in burnt rats after delayed fluid resuscitation. Method: 88 rats were randomly divided into normal control group ( A) , immediate fluid resuscitation group ( B) and delayed fluid resuscitation group ( C) . Rats in groups A and B were subjected to full - thickness thermal injury with an area of 20% TBSA. Their mitochondria respiration state III and IV, respiratory control rate (RCR) , and the activity of NADH - CoQ reductase and succinate dehydrogenase of mitochondria respiratory chain were determined at 1 h, 3 h, 6 h, 24 h and 48 h post injury. Result: 1. After burn, the RCR and the activity of NADH - CoQ reductase in groups B and C were much lower than that in group A ( P < 0. 05), and in group C , NADH - CoQ reductase activity was obviously lower than that in group B ( P < 0. 05). 2. The RCR and the activity of NADH - CoQ reductase in groups B had a compensatory increase in 3 h after resuscitation, but decreased again later. 3. In 3 h after burn, the activity of succinate dehydrogenase in groups B and C did not change obviously ( P > 0.05 ) , but it was much lower than that in group A in the later stage of resuscitation (P < 0. 05 ) , and in group C, succinate dehydrogenase activity was obviously lower than that in group B ( P < 0. 05 ). Conclusion: Delayed fluid resuscitation results in more severe injury of mitochondria respiratory function of myocardial cell in burnt rats.