葛根素对大鼠局灶性脑缺血再灌注后神经细胞凋亡及Bcl-2、Bax蛋白表达的影响

The Effect of Puerarin on Cell Apoptosis and Expression of Bcl-2 and Bax Protein in Focal Cerebral Ischemia-Reperfusion

目的探讨葛根素对大鼠局灶性脑缺血再灌注损伤的保护作用。方法制作大鼠大脑中动脉缺血再灌注模型。40只SD雄性大鼠被随机分为假手术组、缺血组、小剂量葛根素治疗组(小剂量组)、大剂量葛根素治疗组(大剂量组)。应用TTC染色观察梗死体积,应用免疫组化染色及TUNEL染色检测Bcl-2、Bax蛋白表达及凋亡细胞数。结果大、小剂量组梗死体积和凋亡细胞数明显少于缺血组(P<0.01),Bcl-2明显多于缺血组(P<0.01),小剂量组Bax少于缺血组(P<0.05),大剂量组Bax明显少于缺血组(P<0.01)。大剂量组梗死体积和凋亡细胞数少于小剂量组(P<0.05),Bcl-2多于小剂量组(P<0.05)。大、小剂量组Bax无统计学意义(P>0.05)。结论葛根素可通过上调Bcl-2蛋白表达,下调Bax蛋白表达减少脑缺血再灌注后神经细胞凋亡,疗效与剂量有关。

Objective To study the effect of puerarin on the expression of Bcl -2 and Bax protein in focal cerebral ischemia - reperfusion. Methods The rat models were established by middle cerebral artery occlusion （MCAO） and reperfusion. Total of 40 healthy male Sprague Dawley （SD） rates were divided randomly into 4 groups： Sham operation group,cerebral isehemia gioup, large dose of puerarin group and low dose of puerarin group. The iscbemie zone was detected by tetraphenyl tetrzolium chloride staining. The expression of Bcl - 2 and Bax protein were analyzed by immunohistochemistry. The neural cells apoptosis were measured by terminal de- oxynueleotidyl transferase-radiated dUTP nick end labeling （TUNEL）. Results Compared with the cerebral ischemia group, the size of infarct and the number of the neural cells apoptosis in large dose group and lower dose group were decreased remarkably （P〈0.01）, expression of Bcl- 2 was increased obviously （P〈0. 01）, expression of Bax in the lower dose group was decreased（P〈0.05）, and that in the large dose group was increased obviously （P〈0.01）. Compared with the lower dose group, the size of the infarct and the number of the neural cells apoptosis in the large dose group were decreased （P〈0.05）, and expression of Bcl - 2 was increased（P〈0.05）. There were no significant different in Bax protein positive cells in two treatment group （P〈0.05）. Conclusion Puerarin possessed the anti- apoptotic effects which might be related to the reduction the expression of Bax and increasing the expression of Bcl - 2.