狼毒宁B对局灶性脑缺血再灌注损伤大鼠的神经保护作用研究

Neuroprotective Effect of Chamaejasmenin B on the Reperfusion Injury in Rats with Focal Cerebral Ischemia

目的:探究狼毒宁B对局灶性脑缺血再灌注大鼠的神经保护作用。方法:选用健康雄性SD大鼠,线栓法制备大鼠大脑中动脉缺血再灌注(MCAO)模型,缺血2 h后实现再灌注。实验分为假手术对照组、模型对照组、狼毒宁B 5、10、20 mg/kg组和阳性药依达拉奉6 mg/kg组,再灌注后2 h腹腔注射给药。再灌注24 h后进行TTC染色,计算脑梗死体积百分比。再灌注24 h后,利用分光光度法检测大鼠脑缺血核心区与半暗带组织中脂质过氧化物丙二醛(MDA)含量、一氧化氮合酶(NOS)、总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)活性的变化。并于再灌注后1、3、7 d分别使用Zea-Longa’s级标准评分和改良神经功能缺损评分(mNSS)等评价手段,评测狼毒宁B对MACO大鼠不同时期神经功能的变化。结果:与假手术对照组相比,模型对照组大鼠脑缺血核心区与半暗带组织中T-AOC能力、GSH-Px和CAT活力明显降低(P<0.05或P<0.01),MDA含量和NOS活力显著升高(P<0.01)。与模型对照组相比,再灌注24 h后,狼毒宁B 10、20 mg/kg均可显著降低MCAO大鼠脑梗死体积(P<0.01),明显升高大鼠脑缺血核心区与半暗带组织中T-AOC能力、GSH-Px、CAT活力(P<0.05或P<0.01),明显降低MDA含量和NOS活力(P<0.05或P<0.01),10 mg/kg时效果最佳。此外,随着给药时间延长,狼毒宁B能够明显降低MCAO大鼠Zea-Longa’s级标准评分和神经功能缺损评分(P<0.05或P<0.01)。结论:狼毒宁B对脑缺血再灌注损伤大鼠具有一定的神经保护作用,其作用机制可能与改善脑内氧化应激水平有关。

Objective: To explore the neuroprotective effect of Chamaejasmenin B on the focal cerebral ischemia-reperfusion injury in rats. Methods: Healthy male SD rats were selected to establish MCAO model rats by the suture method, and the reperfusion was conducted 2 h later. Rats were divided into the control group, the model group, Chamaejasmenin B group(5,10,20 mg/kg) and Edaravone group(6 mg/kg). 2 hours after reperfusion, the rats were given the intraperitoneal injection of drugs. 24 hours after reperfusion, TTC staining was performed to calculate the percentage of cerebral infarct volume. Moreover, after 24 hours reperfusion, the MDA content and the activities of NOS,T-AOC,GSH-Px and CAT in the ischemic core areas and penumbras of brain tissues of rats were detected by the spectrophotometric method. In addition, 1,3,and 7 days after reperfusion, the Zea-Longa’s standard score and the modified neurological deficit score were used to evaluate the neurological function in different stages. Results: Compared with the control group, T-AOC capacity, GSH-Px activity and CAT activity of MCAO rats in the model group were significantly reduced(P<0.05 or P<0.01),the MDA content and NOS activity were significantly increased(P<0.01). Compared with the model group, the cerebral infarct volumes of MCAO rats in Chamaejasmenin B groups(10,20 mg/kg) were significantly reduced(P<0.01), while 10 mg/kg had the best effect. After 24 hours reperfusion, compared with the model group, T-AOC capacity, GSH-Px activity and CAT activity of MCAO rats in Chamaejasmenin B group were significantly increased(P<0.05 or P<0.01), MDA content and NOS activity were significantly reduced(P<0.05 or P<0.01), while 10 mg/kg had the best effect. In addition, Chamaejasmenin B significantly reduced the Zea-Longa’s standard scores and the neurological deficit scores of MCAO rats as the administration time prolonged(P<0.05 or P<0.01). Conclusion: Chamaejasmenin B has the neuroprotective effect on the cerebral ischemia-reperfusion injury in rats, and its mechanism of action may be related to the improvement of brain oxidative stress.