丁基苯酞对局灶型脑缺血再灌大鼠脑hsp70mRNA和c-fos时相表达的影响

用原位杂交法和Northern印迹法,研究NBP对暂时性大脑中动脉阻断大鼠不同再灌期脑内hsp70mRNA和c-fos的时相表达的影响。发现缺血后再灌1h,在缺血侧有较明显的hsp70mRNA表达。再灌3h,6h和12h,表达逐渐加强。在缺血前10min和再灌即刻ipNBP10mg·kg^-1和20mg·kg^-1均能明显降低再灌6h和12hhsp70mRNA的表达。c-fos基因在再灌0.5h在缺血侧有清晰表达,再灌3h达峰值,再灌6h表达降低。ipNBP10mg·kg^-1(缺血前10min)可明显降低再灌1h和3h时c-fos的表达。Northern印迹法显示了同样的结果。提示NBP降低基因表达的作用可能是通过减轻缺血再灌引起的组织损伤来实现的。

Effect of dl-3-N-butylphthalide on the expression of hsp70 mRNA and c-fos in transient cerebral ischemic and reperfused rat brain]

Transient cerebral ischemia may cause striking changes in gene expression in rat brain. The induction of heat shock protein 70 (hsp70) mRNA is considered to be an important marker of cerebral ischemia injury, and c-fos may upregulate the expression of other genes related to the secondary injuries. dl-3-n-Butylphthaline(NBP) had been shown to have good anti-cerebral ischemic effect. Using the in situ hybridization and Northern blot technique, the effect of NBP on the expression of hsp70 mRNA and c-fos in transient middle cerebral artery occlusion (MCAo) rat caused by intraluminal thread was studied, and found that the expression of hsp70 mRNA was at the lesioned site at 1 h of reperfusion. It increased gradually with the duration of reperfusion time and peaked at 12 h at the lesioned site. With NBP treatment(i.p. 10 mg.kg-1 10 min before ischemia or 20 mg.kg-1 after ischemia), the expression of hsp70 mRNA attenuated significantly. For c-fos, the expression appeared at 0.5 h of reperfusion, peaked at 3 h, and decreased at 6 h. NBP pretreatment (10 mg.kg-1 10 min before ischemia) also decreased the c-fos expression. The same results were obtained with Northern blot technique. Since NBP had been shown to have good anti-cerebral ischemic effects, the attenuating effect on gene expression seemed to be the secondary effect after the alleviation of tissue injury.