Objective: To establish an ex vivo model of myocardial ischemia reperfusion in tree shrews.
Methods: The Langendorff ex vivo heart perfusion system was used to establish the myocardial ischemia reperfusion model in tree shrews with different irrigation and reperfusion time settings. Alanine aminotransferase (ALT), aspartate transaminase (AST) and lactic dehydrogenase (LDH) levels were measured by enzyme-labeled immunosorbent assay, creatine kinase MB (CK-MB) was detected using immunosuppression method, and malondialdehyde was measured with thiobarbital staining method; the infarct size was measured using 2, 3, 5-triphenyltrazoliumchloride (TTC) method.
Results: Ischemia for 30 min and reperfusion for 30 and 60 min caused more significant increase in CK-MB and LDH levels in the perfusion fluid and also in the levels of ALT, CK-MB and AST in the myocardial tissue compared with other experimental settings (P<0.05), but these parameters were comparable between the former two settings (P>0.05). The mean heart rate in 30-min ischemia with 60-min reperfusion group was obviously lower than that in continuous reperfusion group, 15-min ischemia with 30-min reperfusion group and 30-min ischemia with 30-min reperfusion group (P<0.05), and the heart rate was similar between the latter 3 groups (P>0.05). ECG analysis showed that the mean heart rate in 30-min ischemia with 30-min reperfusion group was closer to the physiological heart rate of tree shrews.
Conclusion: We successfully established an ex vivo myocardial ischemia reperfusion model using tree shrews, and ischemia for 30 min followed by reperfusion for 30 min is the optimal experimental setting.
目的: 建立实验树鼩心肌缺血再灌注离体模型。
方法: 采用Langendorff离体心脏灌流系统建立实验树鼩心肌缺血再灌注模型，依据不同的停灌和再灌注时间实验分为5组；酶标法测丙氨酸氨基转移酶（ALT），天冬氨酸氨基转移酶（AST）和乳酸脱氢酶（LDH），免疫抑制法测定肌酸激酶MB同工酶（CK-MB）2，3，5-氯化三苯基四唑染色法（TTC）测定切片梗死面积。
结果: 心肌酶学指标和梗死面积检测发现，停灌30 min再灌注30 min组和停灌30 min再灌注60 min组灌流液CK-MB，灌流液LDH，组织ALT，组织CK-MB和组织LDH等指标均显著高于其它3组（P < 0.05），但两组间差异无统计学意义（P>0.05）。心电分析发现，停灌30 min再灌注60 min组心率显著低于持续灌注组，停灌15 min再灌注30 min组和停灌30 min再灌注30 min组（P < 0.05），而停灌30 min再灌注30 min组心率与持续灌注组和停灌15 min再灌注30 min组差异无统计学意义（P>0.05），停灌30 min再灌注30 min组的离体心脏平均心率更接近于实验树鼩的生理指标。
结论: 实验树鼩心肌缺血再灌注离体Langendorff模型构建成功，停灌30 min再灌注30 min模型效果最好。