干扰素-γ诱导晚期预处理对离体猪心保存质量的影响

Influence of late precondition induced by interfon γ on isolated pig heart

目的评价干扰素-γ(IFN-γ)诱导晚期预处理对离体猪心保存质量的影响。方法20头实验用猪,随机双盲法分为实验组和对照组,实验组予以皮下注射IFN-γ2万U/kg体重,对照组皮下注射生理盐水;测定左室舒张末压力(LVEDP),左室内压力微分(±dp/dt),心肌酶乳酸脱氢酶(LDH),肌酸磷酸激酶(CK-MB)的漏出以及取心肌组织做超微结构分析。4℃冷晶体液保存4h后.温血复灌使离体心脏复跳;分别于复跳15、30、60 min做心功能、酶学检测,60 min取心肌组织做超微结构检测。结果两组心脏的基础LVEDP、±dp/dt、心肌酶LDH、CK-MB以及组织超微结构差异无显著性。冷晶体液保存4 h后,心脏复跳15 min-dp/dt实验组显著高于对照组(P<0.05);30、60 min实验组LVEDP、±dp/dt显著高于对照组(P<0.05);心脏复跳15、30 min LDH、CK-MB的漏出,对照组显著高于实验组(P<0.05);复跳60min后超微结构显示:对照组心肌细胞线粒体、肌原纤维肿胀明显,而实验组心肌细胞线粒体、肌原纤维肿胀变化不明显。结论 提示IFN-γ诱导晚期预处理对4℃冷晶体液保存4 h后的离体猪心具有一定的保护作用。

Objective To evaluate the influence of late precondition induced by IFN-r on isolated pig heart. Methods 20 pigs were randomly divided into two groups: experimental group ( n = 10) receiving INF-r injection (20 000 U/kg) and control group receiving saline solution ( n =10) respectively. 24 h later, before cardiopulmonary bypass (CPB) basic left ventricular function, LDH and CK-MB leakage were measured, and the ultrastructure of myocardium was observed. Then heart was isolated and put into 4℃ cold crystalloid immediately after the blood of pig was taken into CPB machine. Isolated heart was reperfused with warm blood and beat again after preservation for 4 h. Heart beating again lasted for 60 min and afterload of (80-100) cm H2O was given in late 30 min. Left ventricular function and LDH and CK-MB leakage were measured at 15, 30, 60 min after heart beating again and myocardial tissue was taken at 60 min for ultrastructure analyse. Results There was no significant difference between two groups in terms of left ventricular function, LDH and CK-MB leakage, and the ultrastructure before CPB. 15 min after rebeat, -dp/dtmax in experimental group was markedly improved as compared with control group. Both LVEDP and ± dp/dtmax were significantly higher than control group at 30 min and 60 min. LDH and CK-MB leakage were markedly higher in control group. Also in control group, myocardial mitochondria and myofibril were swollen obviously, and karyotheca crimple appeared. In experimental group no obvious changes in ultrastructure were found. Conclusion Late preconditioning induced by IFN-γ has preventive effect on isolated pig heart.