尼莫地平对急性损伤后大鼠背根节细胞c-fos、c-jun mRNA表达的影响

Effects of Nimodipine on the c-fos and c-jun mRNA expressions in dorsal root ganglia of rate following acute injury

目的探讨钙离子拮抗剂尼莫地平对急性外周神经损伤后大鼠背根神经节c-fos、c-jun mRNA表达的影响。方法建立大鼠坐骨神经切断模型,利用逆转录-聚合酶链反应(RT-PCR)半定量法,检测经尼莫地平预处理的大鼠在制模后不同时间(5min、15min、30min、60min、120min),以及同一时间(60min)应用不同剂量(2.5mg/kg、5mg/kg、10mg/kg)尼莫地平时大鼠背根神经节c-fos、c-jun mRNA的表达水平的变化。结果与对照组比较,损伤组c-fos mRNA表达于损伤后30min、60min、120min,c-jun mRNA表达于损伤后15min、30min、60min、120min显著升高(均P<0.05);而尼莫地平组与对照组各时间点c-fos、c-jun mRNA表达比较差异无统计学意义。与损伤组比较,尼莫地平组c-fos、c-jun mRNA表达于30min、60min、120min明显降低(均P<0.001)。不同剂量尼莫地平预处理后,c-fos mRNA的表达随尼莫地平剂量的增加而逐渐减少,各剂量组间比较差异有统计学意义(均P<0.05),c-fos mRNA表达水平与用药剂量呈负相关(r=-2.663,P<0.05);c-jun mRNA表达各剂量组间比较差异无统计学意义,亦无剂量相关性。结论急性外周神经损伤时应用钙离子拮抗剂尼莫地平,早期通过抑制c-fos、c-jun mRNA的表达,对外周神经损伤有一定的保护作用。

Objective To explore the effects of Nimodipine on oncogene c-fos and c-jun mRNA expressions in dorsal root ganglia of rats following acute sciatic nerve injury. Methods Nimodipine at a dose of 10 mg/kg at 5, 15, 30, 60 and 120 rain and at a different dose of 2.5, 5 and 10 mg/kg at 60 min was given to each rat through intraperitoneal injection before transection of sciatic nerve. Using reverse transcription PCR （RT-PCR） technique, the c-fos and c-jun mRNA expressions were detected at 5, 15, 30, 60 and 120 rain after injection of Nimodipine and following acute sciatic nerve injury. Results Compared with control group, the expressions of c-fos mRNA in injury group were obviously increased at 30, 60 and 120 rain after injury （ all P 〈 0. 05 ）. c-jun mRNA expressions were also increased at 15, 30, 60 and 120 rain （all P 〈0. 05）. There was no significant difference in the c-fos and c-jun mRNA expressions between Nimodipine group and control group. Distinctly decreased expressions of c-fos and c-jun mRNA were seen in Nimodipine group at 30, 60 and 120 rain, compared with injury group （ all P 〈 0. 001 ）. In different dose group, the c-fos mRNA expression was gradually reduced with the raise of Nimodipine in dose. It was a remarkable difference between each other group at a different Nimodipine dose of 2.5, 5 and 10 mg/kg （ all P 〈 0. 05）. c-fos mRNA expression was moderately negatively related to the dose of Nimodipine （ r = - 2. 663, P 〈 0. 05 ）. There was no obvious difference in the expression of c-jun mRNA among different dose group. Conclusions Nimodipine can significantly inhibit the c-fos and c-jun mRNA expressions in rat dorsal root ganglia. It may have neuroprotective effect on the early acute peripheral nerve injury period.