周围神经电刺激促进相应脊髓节段及背根神经节表达pCREB和BDNF

Electrical stimulation of peripheral nerve promotes expressions of p CREB and BDNF in spinal segment and dorsal root ganglion

目的研究电刺激促进神经再生的机理,为周围神经电刺激促进脊髓损伤修复治疗策略的建立提供实验依据。方法将切断坐骨神经的雄性SD大鼠24只随机分为对照组(不实施电刺激)和实验组(实施电刺激),每组12只。采用免疫组化技术(荧光法),检测相应脊髓节段及背根神经节中磷酸化环磷酸腺苷反应原件结合蛋白(p CREB)的表达,并对脊髓及背根神经节中阳性神经元进行计数。采用实时定量聚合酶链反应(RT-q PCR)对脑源性神经营养因子(BDNF)mRNA水平进行测定。结果经免疫组化染色发现,术后第3 d实验组脊髓和背根神经节p CREB阳性神经元数大于对照组(P<0.05),且经RT-q PCR分析,术后第3 d实验组脊髓及背根神经节BDNF mRNA水平较对照组明显升高(P<0.05)。结论电刺激作用于周围神经损伤近端,可上调相应脊髓节段及背根神经节神经元内p CREB和BDNF的表达水平。

Objective The mechanism of peripheral nerves regeneration by electrical stimulation （ES） is investigated to provide experimental basis for the construction of clinical therapeutic strategies to promote the recovery after spinal cord injury. Methods Twenty-four male Sprague-Dawley （SD） rats with sciatic nerve cut were randomly divided into control group （without ES, n = 12 ） and experimental group （with ES for 1 h, n = 12）. Expression of phosphorylated cyclic adenosine monophosphate-response element binding protein （pCREB） in spinal segment and dorsal root ganglion （DRG） was measured by immunofluorescence （IF） and the positive neurons were counted. The expression level of brain-derived neurotrophie factor （BDNF） mRNA was observed by real time-quantitative polymerase chain reaction （RT-qPCR）. Results More pCREB positive neurons in spinal segment and DRG were observed in experimental group by IF three days after operation （P 〈 0. 05）. The RT-qPCR analysis indicated that BDNF mRNA level in experimental group was higher than that in control group （ P 〈 0.05 ）. Conclusion ES acting on the proximal end of injured peripheral nerve can significantly increase the expressions of pCREB and BDNF in spinal segment and DRG.