线栓法插线深度对大鼠脑梗死模型制备的影响

Effect of different insertion depths of the nylon thread on the establishment of rat models of middle cerebral artery occlusion

目的比较不同栓线插线深度对线栓法制作大鼠脑梗死模型的影响。方法按照栓线深度将大鼠分为4组:(1)0.8 cm组;(2)1.3 cm组;(3)1.8 cm组;(4)2.2 cm组。模型前、模型后24 h和48 h分别称量体重和行神经损伤严重程度评分;模型后48 h计算各组大鼠存活率,处死大鼠行2,3,5-三苯氯化四氮唑(TTC)染色并计算脑梗死体积。结果 0.8 cm组和1.3 cm组大鼠症状不明显,TTC染色未见脑梗死;1.8 cm组和2.2 cm组大鼠出现典型偏瘫症状,但2.2 cm组大鼠梗死范围过大,存活率较1.8 cm组显著下降(P<0.05)。结论线栓法制作大鼠MCAO模型需要选择合适的插线深度;过浅模型易制作失败;过深则模型症状偏重,存活率降低;最佳深度为栓线头端置于大脑中动脉起始处。

Objective To compare the effects of different insertion depths of nylon thread on the establishment of rat model of middle cerebral artery occlusion（MCAO）.Methods The rats were randomly divided into four groups according to different insertion depths of the nylon thread：（1） 0.8 cm group;（2） 1.3 cm group;（3） 1.8 cm group;（4） 2.2 cm group.The body weight and modified neurological severity scores were tested before MCAO,24 h and 48 h after MCAO.All rats were killed at 48 h after MCAO.The brains were removed and dissected into 6 pieces of 2 mm thick coronal slices.The fresh brain slices were stained by 2% 2,3,5-triphenyltetrazolium chloride and the relative infarct volume was measured.Results The rats of 0.8 cm and 1.3 cm groups showed normal behaviour and without infarction.In contrast,the rats in the 1.8 cm and 2.2 cm groups had typical symptoms of hemiplegy.However,rats in the 2.2 cm group showed lower body weight,higher mortality and increased infarct volume compared with that in the 1.8 cm group.Conclusion Suitable insertion depths of the nylon thread should be selected to make MCAO models.The best depth is that the nylon thread tip is placed at the origin of the middle cerebral artery.