丙戊酸对大鼠脊髓损伤后Caspase-3及C-fos表达的影响

目的探讨丙戊酸（VPA）对大鼠脊髓损伤（SCI）后Caspase-3及c-fos表达的影响。方法 60只雄性sD大鼠随机分为3组：假手术组（C组）、损伤组（SCI组）和丙戊酸保护组（VPA组）。采用改良的Allen法制作脊髓损伤动物模型。VPA组术后即刻及其后每12h皮下注射VPA300mg／kg；C组和SCI组在相应时间点注射等体积的生理盐水。伤后6h，每组取5只大鼠处死取材，每组其余大鼠分别在伤后24、48、72h取5只先行后肢运动功能BBB评分，随后处死取材。通过免疫组化法检测Caspase-3及c-fos的表达。结果 BBB评分显示，C组运动功能未受影响，VPA组的BBB评分均高于SCI组，两者相比在伤后48h和72h差异有显著性（P〈0．05）。与C组相比，SCI组和VPA组的Caspase-3表达在各时间点均明显增加（P〈0．05），而VPA组的增加低于SCI组（P〈0．05）；与C组相比，SCI组和VPA组的c—fos表达在伤后6、24、48h明显增加（P〈0．05），而VPA组的增加也低于SCI组（P〈0．05）。结论VPA可能通过抑制Caspase-3和e．fos表达，从而对SCI发挥保护作用。

Effects of valproic acid on expression of Caspase - 3 and c - fos in rats after spinal cord injury

Objective To investigate the effects of valproic acid （VPA） on the expression of Caspase - 3 and c - fos in rats after spinal cord injury （SCI）. Methods Sixty male rats were randomly divided into three groups：sham operation group （control group） ,injury group（ SCI group） ,and VPA group. Animal models of SCI were made by modified Allen technique. VPA group received the subcutaneous injection of 300 mg/kg VPA immediately after the operation and in every 12 h. control group and SCI group received the same volume of normal saline at the same time points. Five rats in each group were killed 6 h after the injury. Other five ones in the rest rats of each group were killed after they received the BBB scoring for their hind limb function at 24,48, and 72 h after the injury. The expression of Caspase - 3 and c - fos was detected by immunohistochemistry. Results The BBB scores indicated the motor function in control group was not affected. The scores in VPA group were higher than those in SCI group, and there were significant differences at 48 h and 72 h after the injury between the two groups （P 〈 0.05 ）. Compared with the expression of Caspase - 3 in control group, that in SCI group and VPA group increased significantly at each time points（P 〈0.05） ,but the increased expression in VPA group was lower than that in SCI group（ P 〈 0.05 ）. Compared with the expression of c - fos at 6,24, and 48 h after the injury in control group, that in SCI group and VPA group increased significantly （P 〈 0.05 ）, but the increased expression in VPA group was lower than that in SCI group（P 〈 0.05）. Conclusion VPA can play a protective role in SCI through inhibiting the expression of Caspase - 3 and c - fos.