大鼠后肢急性缺血模型的构建及评估

Construction and evaluation of rat hindlimb acute ischemia model

目的探讨大鼠后肢急性缺血后血流、血压的动态变化及肌肉组织的变化,为进行后续干预实验摸索条件。方法取Lewis大鼠10只采用切除左后肢股动脉及其分支至膝关节附近的方法制备急性后肢缺血模型,分别于术后2,7,14,28,42,49 d对患侧和健侧肢体进行血流、血压及血管造影分析。取材后行后肢肌肉HE常规染色,观察病理变化。结果动物术后均成活,但部分出现后肢跛行(n=2),紫绀(n=2),苍白(n=3),肌肉的萎缩(n=1)。急性缺血下肢部分肌肉坏死,大量炎性细胞浸润;后期出现纤维化。患肢血流在术后7 d明显下降,术后28 d下降至最低点,术后49 d基本恢复正常(正常肢体的90%)。患肢血压在术后2 d明显下降,14 d下降至最低点,后逐渐恢复,至49 d基本恢复正常。结论结扎并切除大鼠后肢股动脉及分支可以成功制备下肢缺血模型,但血流及血压在术后42～49 d基本恢复正常,术后14～28 d是缺血最严重的阶段,适于进行各种干预实验研究。

Objective To investigate the effect of dynamic changes of blood flow and blood pressare, and changes of muscle tissues on rat hindlimb acute ischemia, and provide conditions for study on consequent intervention. Methods An acute hindlimb ischemia model was prepared in 10 rats by ligation and excision of left femoral artery and its branches. Doppler scan blood flow and pressure analysis were performed 2 d 7 d, 14 d, 28 d, 42 d, and 49 d after operation. The animals were sacrified post-angiography. H. E stain of muscles was then done. Results All the animals survived after operation. Some showed intermittent elandication and cyanosis （ n = 2 ） , pallor （ n = 3 ） , and muscle atrophy （ n = 1 ） . Tissue examination showed there was necrosis and inflammation of skeletal muscle. The blood flow markedly decreased 7days after operation, reached to the lowest point at 4weeks, and recovered almost 90% at 49days after operation. The blood pressure, which reached the lowest at 14 days, recovered to normal at 49 days. Conclusions It is feasible to establish rat hindlimb isehemia model by ligation and excision of femoral artery, but blood flow and pressure can recover after 49days, and the time for intervention is 2 - 4 weeks after operation, when is the most serious isehmia time.