摘要
目的:探讨不同时间开始给予极化液(葡萄糖-胰岛素-钾液,G IK)对犬心肌缺血/再灌注(M I/R)后心脏功能及心肌细胞损伤的影响。方法:制备犬M I/R模型,心肌定量缺血(左前降支血流量降低80%)50 m in,再灌注4 h。分别于:①再灌注前30 m in(再灌注前)、②再灌注即刻(再灌注时)、③再灌注后1 h(再灌注后)给予G IK。观察对动脉血压、心率、左室压的影响及测定心大静脉血清乳酸脱氢酶(LDH)、肌酸激酶(CK)活性,再灌注结束后检测心肌梗死率或细胞凋亡指数。结果:与再灌注后组相比,再灌注前组和再灌注时组可明显改善再灌注后左室收缩及舒张功能,降低血清CK、LDH活性,减少心肌梗死范围[分别为(5.9±1.1)%和(5.2±0.8)%vs(9.1±1.2)%,均P<0.01]、抑制心肌细胞凋亡的发生[(4.6±0.9)%和(3.7±1.1)%vs(8.9±2.3)%,均P<0.05]。结论:再灌注早期给予G IK可降低M I/R引起的心肌细胞损伤,促进再灌注后心脏功能的恢复,在再灌注后1 h给予G IK对心脏的上述保护作用则明显减弱。
AIM： To investigate whether glucose-insulin-potassium （GIK） cocktail given at different occasion will influence the effects of GIK on cardiac myocyte injury and cardiac functional recovery following myocardial ischemia/ reperfusion （MI/R）. METHODS： The left anterior descending coronary artery was partially occluded （80% reduction in blood flow） in anesthetized open-chest dogs, and then dog was subjected to 50 rain myocardial ischemia followed by reperfusion for 4 h. GIK （ glucose： 250 g/ L, insulin： 60 U/L, potassium： 80 mmol/L, infused at 2 ml/kg·h, i. v. ） was randomly given began at 30 min before reperfusion （Pre-R）, the begim,ing of reperfusion （Rep）, 1 h after reperfusion （R-1 h） and continuing through the 4 h reperfusion. Arterial blood pressure and left ventricular pressure were monitored throughout the experiment. The activities of CK and LDH were assayed spectrophotometrically. Myocardial infarction and cardiac myocyte apoptosis were determined at the end of reperfusion. RESULTS： MI/R caused significant cardiac dysfunction and myocardial damage （both necrosis and apoptosis）. Compared with the R-1 h group, the Pre-R and Rep groups showed cardiac protection against ML/R as evidenced by the improved recovery of cardiac systolic/ diastolic function, significant decrease of serum creatine kinase （ CK ） and lactate dehydrogenase（ LDH ）, reduced myocardial infarction [ （ 5.9 ± 1.1）%, （5.2±0.8）% vs （9.1±1.2）% of R-1 h,P〈0.05], decreased apoptosis index[（4.6± 0.9）%, （3. 7 ± 1. 1 ）% vs （8. 9 ± 2. 3）% of R-1 h,P 〈 0. 05] at the end of reperfusion. CONCLUSION： GIK exerts by improving cardiac functional recovery and reducing myocardial injury, where as the cardioprotective effect is significantly attenuated when GIK was given 1 h after reperfusion.
出处
《心脏杂志》
CAS
2005年第5期419-423,共5页
Chinese Heart Journal
基金
国家自然科学基金资助(No.30370525
No.30471923)
关键词
极化液
缺血/再灌注
心肌梗死
凋亡
glucose-insulin-potassium
ischemia/reperfusion
myocardial infarction
apoptosis
