局灶性脑缺血再灌注认知功能变化的实验研究

Cognition alteration of rats after focal cerebral ischemia-reperfusion injury

目的观察不同时相缺血再灌注的大脑中动脉闭塞大鼠模型认知功能的变化。方法36只SD大鼠,雌雄各半,分为假手术组、缺血30 m in再灌注组、缺血90 m in再灌注组。采用Longa线栓法制成年SD大鼠大脑中动脉闭塞(MCAO)模型。通过观察大鼠神经行为学评分、术后14 d红四氮唑(TTC)染色、水迷宫及听觉事件相关电位(P300)对认知功能的变化进行研究。结果缺血30 m in再灌注组、缺血90 m in再灌注组大鼠神经行为学评分都在2分以上。大鼠术后第14天,TTC染色的结果显示2组缺血再灌注组大鼠的脑组织均有梗死灶。在定位航行实验、空间探索实验和听觉事件相关电位(P300)中,缺血90 m in再灌注组大鼠和假手术组、缺血30 m in再灌注组大鼠都存在明显差异(P<0.01)。结论局灶性脑缺血再灌注大鼠的认知功能下降并随缺血时间的不同呈正相关改变。

Objective To （MCAO） rats, following varied observe the changes of cognition ability of the middle cerebral artery occlusion lengths of cerebral ischemia-reperfusion. Methods Totally 36 SD rats （female or male） were randomly and equally divided into 3 groups, the sham group, the ischemia 30 min group and the ischemia 90 min group. The model of MCAO was made by occluding the MCA with thread according to Longa＇ s method. Behavioral assessment was evaluated by neurological test. Brain tissue damage was detected in the ischemia animals 14 d after the surgery by triphenyl tetrazolium chloride （TTC） staining. Cognition ability was determined by Morris-maze test and P300 test. Results The score of neurological test were both over 2 points of ischemia groups of 30 min and 90 min. And both groups had infarct areas by TTC staining. The results of Morris-maze test and P300 test showed that the ischemia 90 min group were improved significantly in comparison with sham group and the ischemia 30 min group （P 〈 0. 01 ） . Conclusion Focal cerebral ischemia can result in the cognitive impairment, which is worse along with the extension of ischemic period.