再生小室内间断给予蛋白激酶C激动剂对周围神经表达NGF及损伤修复的影响

EXPRESSION OF NERVE GROWTH FACTOR mRNA AND NERVE REGENERATION AFTER DISCONTINUOUS INJECTION OF PHORBOL-12-MYRISTATE-13-ACETATE INTO SILICONE CHAMBER

目的 探讨大鼠坐骨神经再生小室内间断给予蛋白激酶 C激动剂 -佛波醇酯 ( phorbol- 12 - myristate-13- acetate,PMA)后 ,坐骨神经蛋白激酶 C( protein kinase C,PKC) m RNA、神经生长因子 ( nerve growth factor,NGF)m RNA表达变化规律及轴突数目变化。 方法 SD大鼠 4 2只行双侧坐骨神经中段切断约 5 mm,“T”形硅胶管套接 ,随机分为 6组 ,分别为损伤 1、3天 ,1、2、3和 4周组。右侧间断给予 1× 10 - 9mol/ L PMA( PMA侧 ) ;左侧注射等量生理盐水(对照侧 )。采用组织切片核酸原位杂交 ( in situ hybridization,ISH)技术检测各组术后各不同点 PKC m RNA和 NGFm RNA在坐骨神经表达的动态变化及轴突数目变化。 结果 对照侧大鼠坐骨神经 PKC m RNA在损伤后表达上调 ,第2周达高峰后下降 ;NGF m RNA在损伤后表达上调 ,第 3周达高峰值后下降。PMA侧 PKC m RNA于第 2、3和 4周表达较对照侧明显增高 ,差异有统计学意义 ( P<0 .0 1或 P<0 .0 5 ) ;NGF m RNA第 2、3和 4周表达也较对照侧明显增强 ,差异有统计学意义 ( P<0 .0 1)。轴突数目在 2、3和 4周时多 ,差异有统计学意义 ( P<0 .0 1)。 结论 PKC介导了周围神经损伤修复中的 NGF m RNA表达及神经再生 ,而且 PMA能够促进 NGF m

Objective To study the mRNA expressions of protein kinase C(PKC) and nerve growth factor (NGF) in rat sciatic nerve and the number of axons after phorbol 12 myristate 13 acetate (PMA) was injected into silicone chamber. Methods Forty two SD adult rats were divided into six groups depending on the time of injury (1 day, 3 days, 1 week, 2 weeks, 3 weeks and 4 weeks). A 0 5 cm nerve was cut in double rat sciatic nerves and 'T' type silicone chamber was sutured. PMA at the concentration of 1×10 -9 mol/L was injected discontinuously into the right side of T type silicone chamber(PMA group) and saline was injected into the left side(control group). Nucleic acid in situ hybridization histochemistry technique and the computer imagine analysis were employed to detect dynamic changes of PKC mRNA and NGF mRNA in rat sciatic nerves. The number of axons was measured. Results The expressions of PKC mRNA and NGF mRNA increased after injury, and the expressions of PKC mRNA and NGF mRNA reached the peak 2 weeks and 3 weeks after injury respectively in control group. The expressions of PKC mRNA and NGF mRNA in PMA group were significantly increased than those in control group 2,3 and 4 weeks after injury ( P <0 01). The number of axons in PMA group significantly increased than that in control group( P <0.01). Conclusion PKC involved in the expression of NGF mRNA and nerve regeneration after injury. During the regenerated course, PMA can promote the expression of NGF mRNA and the number of axons after injury.