Abstract: Objective To study the effect of vinpocetine injection on the neurological function recovery and microglia polarization after permanent ischemia of distal middle cerebral artery(MCA) in mice. Methods Thirty six male C57BL/6J mice were randomly divided into permanent cerebral ischemia group (n =6), normal saline group (n =12), vinpocetine group (n =12) and sham group (n =6). The distal right MCA occlusion models were established by electrocoagulation in the first three groups. In the sham group, the distal of the MCA was exposed without electrocoagulation.Vinpocetine injection (4.55 mg/kg, 150 μL) or equal volume normal saline was injected via the caudal vein

20 minutes after ischemia for 5 minutes, and was administered continuously once a day for 14

days. Modified Garcia scores and rotarod test were performed to evaluate the sensory and motor neurological function of mice at 3, 7, 9, 11 and 14 days after the surgery. Neuron injury and Iba1 with CD16/32 (M1 microglia, pro-inflammatory) or CD206 (M2 microglia, anti-inflammatory) expression in cortex were evaluated by immunofluorescence staining at 14 days after ischemia. Results Vinpocetine injection improved modified Garcia scores at 11 and 14 days, quickened the running time and increased the speed of rotarod test at 14 days, compared with permanent cerebral ischemia group, with all statistical differences. Vinpocetine injection alleviate neuron injury compared to the permanent cerebral ischemia group (P =0.008) and normal saline treatment group (P =0.039). Vinpocetine injection decreased the expression of M1 microglia compared to the permanent cerebral ischemia group (P <0.001) and normal saline treatment group (P =0.038), and increased the expression of M2 microglia, compared to the other three groups (all P <0.001). Conclusions Vinpocetine injection may have protective effect against cerebral ischemia injury after permanent cerebral ischemia in mice by regulating microglia M1/M2 polarization from proinflammatory to anti-inflammatiory response.

Key words: Cerebral ischemia; Vinpocetine; Distal middle cerebral artery occlusion; Microglia polarization; Mouse

摘要： 目的 研究长春西汀注射液对小鼠永久性大脑中动脉远端缺血后神经功能恢复及小胶质细胞表型 转化的影响。 方法 36只雄性C57BL/6J小鼠随机分为永久性脑缺血组6只、生理盐水组12只、长春西汀组12只和 假手术组6只，前三组用高频电刀凝断小鼠右侧大脑中动脉远端，制作永久脑缺血模型，假手术组 仅暴露大脑中动脉远端，不凝断血管。模型成功后，生理盐水组尾静脉注射生理盐水，每次150 μL， 每天1次，持续14 d；长春西汀组尾静脉注射长春西汀注射液，每次150 μL（4.55 mg/kg），每天1次， 持续14 d。模型成功后3 d、5 d、7 d、9 d、11 d和14 d进行改良加西亚评分和转棒测试评价小鼠感觉和 运动神经功能；模型成功后14 d用免疫荧光标记神经元，评价各组神经元损伤情况，免疫荧光染色 梗死周围小胶质细胞表型标志物Iba1、CD16/32和CD206的表达，评价M1型（Iba1及CD16/32阳性）和 M2型（Iba1及CD206阳性）小胶质细胞表型转化情况。 结果 长春西汀组小鼠模型成功后11 d和14 d的改良加西亚评分和14 d的转棒测试中的时间及速度 测试结果均优于永久性脑缺血组，差异均有统计学意义。长春西汀组14 d时神经元损伤较永久性脑 缺血组（P =0.008）和生理盐水组（P =0.037）减轻。永久缺血组（P <0.001）和生理盐水组（P =0.005） M1型小胶质细胞表达高于假手术组；长春西汀组M1型小胶质细胞表达低于永久缺血组（P <0.001） 和生理盐水组（P =0.038）。长春西汀组M2型小胶质细胞表达高于假手术组、永久性脑缺血组和生 理盐水组（均P <0.001）。 结论 长春西汀注射液可能通过促进小胶质细胞表型由促炎向抗炎转变，减少神经元损伤，从而 在小鼠永久性脑缺血后发挥神经保护和促进功能恢复的作用。

关键词: 脑缺血; 长春西汀; 大脑中动脉远端栓塞; 小胶质细胞极化; 小鼠