小鼠局灶性缺血再灌注模型的插线法试验(英文)

An experiment on focal cerebral ischemia reperfusion model in mice established with suture method

背景:国外小鼠局灶性脑缺血模型技术已经成熟,由于条件限制国内现多以大鼠制作脑缺血模型。目的:建立小鼠局灶性脑缺血再灌注模型,以适应在基因水平进行脑缺血和再灌注损伤分子机制的研究。设计:随机对照实验。单位:承德医学院基础医学研究所。材料:实验于2002-09／2003-05在承德医学院基础研究所完成。选择 18只昆明小鼠2-3月龄,体质量20-25 g,雌雄兼用。分为假手术缎、缺血3 h再灌18 h和24 h组,每组6只。干预:通过神经病学评分,红四氮唑染色及病理形态学的观察,对造模的可靠性进行评价。选用尼龙钓丝(φ0.128mm)经过液体石蜡浸泡后, 从颈外动脉向颈内动脉插入,阻断小鼠右侧大脑中动脉3 h后,拔出线栓再灌注18 h和24 h。主要观察指标:小鼠脑梗死体积及神经学评分。结果:实验共18只小鼠均进入结果分析。①假手术组未出现神经缺损症状。②手术组小鼠神经症状表现为提尾悬空时头向左歪,左前肢内收、肩内旋,左前肢肌张力降低,不能完全伸直,自主活动时,以左后腿为圆心向左旋转,左前肢压在腹下与右前肢交叉成剪刀状,左侧肢体瘫痪更为明显,尤其是前肢,神经症状随再灌注时间延长而加重。③红四氨唑染色可清晰地显示出脑梗死范围,缺血3 h再灌18 h梗死体积为(13+2.3)mm3,缺血3 h再灌注24 h梗死体积为(16+4.5)mm3,并相对稳定,光学显微镜下可见脑缺血后的病理改变。阻断3 h再灌18,24 h 后病理损伤性改变随时间延长加重。结论:插线法制作小鼠脑缺血再灌注模型无需开颅,创伤小,缺血的部位较恒定、可以准确控制缺血和再灌注时间,此模型可做为观察脑血管疾病的病理生理改变、预后及药物治疗作用的理想实验动物模型。

BACKGROUND： Techniques in the focal cerebral ischemia model in mice have been well developed in some foreign countries. However, rats are commonly used in cerebral ischemia studies due to resource availability in China. OBJECTIVE： To establish reliable and reproducible focal cerebral ischemia reperfusion model in mouse to explore the molecular mechanism of cerebral ischemia reperfusion process in genetic level. DESIGN： Randomized controllod study. SETTING： Fundamental Medical Research Institute of Chengde Medical College. MATERIALS： The experiment was carried out in Fundamental Medical Research Institute of Chengde Medical College from September 2002 to May 2003. Totally 30 Kunming mice （25 to 30 g）, provided by Experimental Animal Center, Chengde Medical College, were randomly grouped as follows： control group, 6, 3-hour occlusion and 18-hour, 24-hour reperfusion, with 6 mice in each group respectively. INTERVENTIONS： Nylon thread （qb0.128 mm） was soaked in paraffin wax and inserted into internal carotid artery in mouse to reversibly occlude the middle cerebral at the right side after 3 hours, then was removed, and reperfusion was performed in 18, 24 hours, respectively. MAIN OUTCOME MEASURES： The infarct volume was observed and neurological deficit scored was analysis. RESULTS： Data of total 18 rats was entered the final analysis.① Neurologic defect was shown in the sham operation group. ② Neural symptom of mice in operation group was shown as head turning to left, adduction of left forelimb, internal rotation of shoulder, decrease of muscular tension of left forelimb, unable to straighten completely during tail lifted. At independent activity, mice turned to left as the left hidlegs as the center of a circle; under the abdomen, left forelimb was crossed with right forelimb as scissor shape. Palsy of left limbs was observed obviously, especially forelimb. Neural symptom was worse along time lasting. ③ Area of cerebral infarction was shown clearly with TTC. The infarct volumes were （13±2.3） mm^3 and （16±4.5） mm^3 for 18 hours and 24 hours reperfusion and 3-hour isehemia, respectively. Pathological changes were observed under light microscope after ischemia. The infarct volume increased as the increasing of reperfusion time, including 3-hour blocking and 18-hour and 24-hour reperfusion. CONCLUSION： Using suture method to establish focal cerebral ischemia reperfusion model in mice, it is less invasion and trauma without requiring skull opening. Ischemia position is relatively fixed, thus, isehemia reperfu- sion time can be controlled precisely. It is also an ideal animal model to study pathological changes in cerebral vascular diseases and an efficient tool to study the therapeutic effect of medicine after surgery.