川芎嗪预先给药对胎鼠海马神经细胞缺氧/复氧时c-fos和HSP70表达的影响

Effect of tetramethylpyrazine pretreatment on the expression of c-fos and heat shock protein 70 during hypoxia-reoxygenation in cultured fetal rat hippocampal neurons

目的 探讨川芎嗪预先给药对胎鼠海马神经细胞缺氧/复氧时c-fos和热休克蛋白70（HSP70）表达的影响.方法 胎鼠海马神经细胞培养鉴定后,随机分为5组（n=24）：正常对照组（C组）、缺氧/复氧损伤组（A/R组）、不同浓度川芎嗪预先给药组（L组、M组和H组）.C组不制备缺氧/复氧模型;A/R组、L组、M组和H组制备缺氧/复氧模型;L组、M组和H组加入川芎嗪,终浓度分别为60、200和800μg/ml,孵育1 h后制备缺氧/复氧模型.缺氧/复氧模型制备方法：海马神经细胞置入90%N2-10%CO2培养箱中孵育2 h诱导缺氧,然后放入37 ℃、5%CO2培养箱中复氧24 h.处理结束后测定海马神经细胞凋率、细胞活力、c-fos和HSP70的表达水平.结果 与C组比较,A/R组、L组和H组海马神经细胞活力降低,细胞凋亡率升高（P＜0.01）;与A/R组比较,L组、M组和H组海马神经细胞活力升高,细胞凋亡率降低,c-fos表达下调,HSP70表达上调（P＜0.05）;与L组比较,M组和H组海马神经细胞活力升高,细胞凋亡率降低,c-fos表达下调,HSP70表达上调（P＜0.05）;与M组比较,H组细胞活力下降,细胞凋亡率升高,c-fos表达上调,HSP70表达下调（P＜0.01）.结论川芎嗪预先给药抑制胎鼠海马神经细胞缺氧/复氧时细胞凋亡的机制可能与下调c-fos表达,上调HSP70表达有关.

Objective To investigate the effect of tetramethylpyrazine pretreatment on the expression of cfos and heat shock protein （HSP70） during hypoxia-reoxygenation （H/R） in cultured fetal rat hippocampal neurons. Methods After the neurons were cultured and identified, they were randomly divided into 5 groups （ n = 24each）： control group （group C）, H/R group, and low, median and high concentration of tetramethylpyrazine pretreatment groups （group L, M and H）. The neurons were exposed to 2 h of hypoxia followed by 24 h of reoxygenation. Tetramethylpyrazine was added with the final concentrations of 60, 200 and 800 μg/ml in group L, M and H respectively, and then the neurons were incubated for 1 h before H/R. The apoptosis rate, cell viability and expression of c-fos and HSP70 were detected. Results The cell viability was significantly lower, while the apoptosis rate was significantly higher in group A/R, L and H than in group C （P 〈0.01）. The cell viability and HSP70expression were significantly higher, while the apoptosis rate and c-fos expression were significantly lower in group L, M and H than in group A/R, and in group M and H than in group L （P〈 0.05）. The cell viability and HSP70expression were significantly lower, while the apoptosis rate and c-fos expression were significantly higher in group H than in group M （ P 〈 0.01 ）.Conclusion The mechanism by which tetramethylpyrazine pretreatment inhibits the apoptosis in cultured fetal rat hippocampal neurons during H/R may be related to the dowm-regulation of c-fos expression and up-regulation of HSP70 expression.