探讨改良线栓对局灶脑缺血模型制备的影响

时间:2020-10-06 19:29:16 药学毕业论文 我要投稿

探讨改良线栓对局灶脑缺血模型制备的影响

【摘要】 目的: 探讨改良线栓对局灶脑缺血模型制备的影响,评价该模型的稳定性和可靠性. 方法: 雄性Wistar大鼠40只随机分为常规线栓组和改良线栓组,每组20只. 线栓法制备右侧大脑中动脉闭塞(MCAO)致局灶脑缺血模型. 观察改良线栓对总体手术时间、术中颈总动脉血流阻断时间、线栓误入翼腭动脉(PPA)几率(PPA误栓率)和模型成功率的影响,并通过神经行为学评分、红四氮唑(TTC)染色和磁共振检测等方法评价该模型的稳定性和可靠性. 结果: 改良线栓组比常规线栓组总体手术时间和术中颈总动脉血流阻断时间明显缩短,线栓误入PPA的几率降低,模型成功率高,稳定可靠. 结论: 改良线栓可增加模型成功率,提高局灶脑缺血模型的稳定性和可靠性.
【关键词】 脑缺血;疾病模型,动物;缝合技术;大脑中动脉闭塞;大鼠

  【Abstract】 AIM: To investigate the application of modified suture in preparation of rat model of focal cerebral ischemia and to evaluate the stability and reliability of the model. METHODS: 40 Wistar male rats were randomized into the conventional suture group and the modified suture group, with 20 in each group. The focal cerebral ischemia by MCAO was induced according to Longa?s suture method. The effects of the application of modified suture on the total operation time, the common carotid artery blood occlusion time during the course of operation, the probability that suture entered the pterygopalatine artery (PPA) and the success rate were observed. And the stability and the reliability of the model were evaluated by neurological deficit score, magnetic resonance image, triphenyltetrazolium chloride (TTC) staining in all rats. RESULTS: The total operation time and the common carotid artery blood occlusion time in the modified suture group were obviously shorter than those in the conventional suture group. And the application of modified suture in the model cut down the probability that the suture entered PPA, and increased the success rate, the stability and the reliability of the model. CONCLUSION: The application of modified suture could improve the success rate, the stability and the reliability of the rat focal cerebral ischemia induced by MCAO.
  【Keywords】 brain ischemia; disease models, animal; suture techniques; middle cerebral artery occlusion; rats
  0 引言

  大鼠的基因与人类的基因具有98%的同源性,其脑血管结构与人类非常相似,血管闭塞后缺血范围恒定、重复性好. 因此,众多有关脑缺血的研究均选用大鼠来制备模型[1-2]. 制备大鼠局灶脑缺血模型的方法较多,但以线拴法应用最广. 线栓法制备局灶脑缺血模型目前还存在某些不足,如线栓插入困难,栓塞成功率不高,梗塞体积不稳定等[3]. 这与线栓直径、弧度以及术中颈总动脉血流阻断时间等因素密切相关.本研究重在对线栓弧度进行改良,观察改良线栓对局灶脑缺血模型的'影响.
  1 材料和方法
  1.1 材料 健康雄性Wistar大鼠40只,体质量220~250 g,8~10 wk龄,购自重庆医科大学实验动物中心,适应性喂养1 wk后,随机分为常规线栓组和改良线栓组,每组20只.

  选用“贵花田”牌鱼线,直径0.23~0.26 mm,参照Ma等[4]的方法略加修改,制备改良线栓. 先将鱼线剪成3 cm长的小段,60~70℃加热2 h将鱼线小段塑呈弧形,弧形外切角为30°时最佳,可确保线栓弧度与大鼠颈内动脉走行一致. 自然冷却后,头端约5 mm涂上聚胺酯,用油性记号笔在线栓头端和距头端约2 cm处作上标记,以方便植入线栓时调整线栓方向,了解线栓进入血管的长度. 制备常规线栓时,除不进行加热塑型外,其余步骤相同.制备好的线栓头端向上,垂直插在海绵垫上,风干,紫外线消毒后备用. 使用前在生理盐水配制的肝素钠(6250 u/mL)溶液中浸渍可用.