巴豆叶对脑缺血再灌注大鼠海马组织ERK1/2蛋白表达的影响

Effects of Croton leaf on ERK1/2 protein expression in hippocampus of rats with cerebral ischemia reperfusion

目的探讨巴豆叶对脑缺血再灌注模型大鼠海马组织ERK1/2蛋白表达的影响。方法将216只SD雄性大鼠按随机数字表法分为假手术组、模型组、尼莫地平组及巴豆叶低、中、高剂量组,每组36只。采用线栓法制备大鼠大脑中动脉栓塞(MACO)模型。巴豆叶高、中、低剂量组灌胃巴豆叶水煎液0.06、0.12、0.18 g/ml,尼莫地平组灌胃尼莫地平混悬液1.08 g/L,假手术组和模型组灌胃等体积的生理盐水。连续给药7 d后,以Garcia JH评分法进行神经功能评分,HE染色观察海马神经元形态,TUNEL法检测海马CA3/DG区细胞凋亡,Western Blot检测海马ERK1/2、p-ERK1/2蛋白表达。结果与同时点模型组比较,巴豆叶低、中、高剂量组神经功能评分升高(P<0.01),凋亡细胞数降低(P<0.01),海马p-ERK1/2/ERK1/2[1 d:(0.22±0.03)、(0.34±0.02)、(0.46±0.01)比(0.19±0.02);3 d:(0.38±0.02)、(0.50±0.02)、(0.68±0.02)比(0.27±0.02);7 d:(0.29±0.03)、(0.43±0.02)、(0.59±0.02)比(0.21±0.03)]蛋白表达上调(P<0.01)。结论巴豆叶可上调ERK1/2通路蛋白表达,有效改善MCAO大鼠神经功能损伤,减少海马CA3/DG区细胞凋亡。

Objective To analyze the effect of Croton leaf on ERK1/2 pathway in hippocampal of rats with cerebral ischemia-reperfusion.Methods A total of 216 SD male rats were divided into sham operation group,model group,nimodipine group,low-dose,medium-dose and high-dose groups of croton leaf according to random nubmer table method,with 36 rats in each group.The MACO model of rats was prepared by the method of wire embolization.The high,medium and low dose groups were intragastrated with the water decoction 0.06 g/ml,0.12 g/ml and 0.18 g/ml of Croton leaf;nimodipine group was intragastrated with nimodipine suspension 1.08 g/L;sham operation group and model group were intragastrated with equal volume of normal saline.Garcia JH score was used to conduct neurological function score,and HE staining was used to observe the morphology of hippocampal neurons after 7 days of continuous administration.Apoptosis of hippocampal CA3/DG region was detected by TUNEL assay.Western Blot was used to detect the expression of ERK1/2 and p-ERK1/2 proteins.Results Compared with the model group at simultaneous point,the neurological function scores of low-dose,medium-dose and high-dose groups of Croton leaf increased(P<0.01),the number of apoptotic cells decreased(P<0.01),the expression of p-ERK1/2/ERK1/2[1 d:(0.22±0.03,0.34±0.02,0.46±0.01 vs.0.19±0.02);3 d:(0.38±0.02,0.50±0.02,0.68±0.02 vs.0.27±0.02);7 d:(0.29±0.03,0.43±0.02,0.59±0.02 vs.0.21±0.03)]in hippocampus of the low-dose,medium-dose and high-dose groups of Croton leaf significantly increased(P<0.01).Conclusion Croton leaf could regulate the expression of ERK1/2 pathway protein upward,effectively improve the neural function and resist the apoptosis of hippocampal CA3/DG area of rats with cerebral ischemia-reperfusion injury.