线栓法建立大鼠局灶性脑缺血模型的改进

Improvement of intraluminal suture method for establishment of focal cerebral ischemic rat models

目的对常规线栓法制作大鼠脑缺血模型进行改进,以提高模型动物的长期存活率。方法将60只体质量250～270 g的SD雄性大鼠随机分成3组,每组20只;对照组采用常规手术方法,术中显露并结扎翼腭动脉,术后自主进食;灌胃组手术方法同对照组,但术后辅助灌胃;改良组不结扎翼腭动脉,但仔细分离颈部动脉与迷走神经,尽量避免操作时牵拉迷走神经,术后辅助灌胃。在模型制作前、后,连续称量各组大鼠的体质量,并行神经功能缺损评分;在造模后3、14、28 d,分别计算各组大鼠的存活率;造模后28 d,计算各组大鼠的脑梗死体积。结果①改良组模型制作的平均时间为19.5 min,低于对照组和灌胃组,差异有统计学意义,P<0.05;②造模后第3天,改良组大鼠的存活率均高于对照组和灌胃组,差异有统计学意义,P<0.05;造模后第28天,改良组大鼠的存活率高于对照组,差异有统计学意义,P<0.05;③造模后3组大鼠的体质量均下降,从造模后第7天开始,各组存活大鼠的体质量均开始回升,在第7、14、21、28天,改良组大鼠的体质量均高于对照组和灌胃组,差异有统计学意义,P<0.05;④造模后3组大鼠的神经功能缺损评分和脑梗死体积的比较,差异均无统计学意义。结论改进的脑缺血模型制作方法,可缩短制作时间,使大鼠体质量恢复较快,能有效地提高大鼠脑缺血造模后的存活率。

Objectives To improve the procedures for establishment of focal cerebral ischemic rat models with the intraluminal suture method and to elevate the survival rate of the models. Methods Sixty male SD rats （weight, 250 -270 g） were randomly allocated into 3 groups （n = 20 in each group）. Control group used the conventional surgical method, the pterygopalatine arteries were exposed and ligated during the procedure, and the rats had free access to food after the procedure; gavage group used the same method as the control group, but postoperative gavage was performed; protective group did not ligate the pterygopalatine arteries, but the carotid arteries and vagus nerves were carefully separated. Trying to avoid stretching the vagus nerves during the procedure and postoperative gavage was performed. The body weight of the rats in each group was weighed continuously before and after modeling, and the neurological deficit scores were measured; the survival rate of rats in each group was calculated at day 3, 14, and 28, respectively after modeling; the brain infarct volume in each group was calculated at day 28 after modeling. Results ①The mean time of model production was 19. 5 min in the protective group, and it was shorter than that in the control and gavage groups. The differences were statistically significant （P 〈 0. 05） ; ②At day 3 after modeling, the survival rate of the rats in the protective group was higher than that in the control and gavage groups. The differences were statistically significant （P 〈 0. 05） ; ③After modeling, the body weight of the rats in the 3 groups were all decreased. The body weight of the rats in each group began to increase from day 7 after modeling. The body weight of the rats in the protective group was all higher than that in the control and gavage groups at day 7, 14, 21, and 28 after the procedure. The differences were statistically significant （ P 〈 0. 05 ） ; ④there were no significant differences comparing the neurological deficit scores and cerebral infarction volume among the 3 groups. Conclusion The improved procedures could shorten the time of model production, regain body weight quickly, improve the survival rate effectively after establishment of the cerebral ischemic rat models.