腰5脊神经结扎大鼠腰4背根神经节神经元超极化激活电流的变化

CHANGE OF Ih IN LUMBAR 4 INTACT DRG NEURONS AFTER L5 SPINAL NERVE LIGA-TION IN RATS

摘要:

目的:研究腰5脊神经结扎(L5spinal nerve ligation,SNL)神经病理痛大鼠腰4背根神经节(dorsal root ganglion,DRG)神经元超极化激活电流(Ih)及其通道超极化激活环核苷酸门控阳离子通道(HCN)发生的可塑性变化。方法:以单侧L5SNL制备神经病理痛大鼠模型,运用全细胞膜片钳技术记录和分析背根神经节神经元Ih的表达和激活特性。结果:L5SNL之后,腰4 DRG神经元Ih的电流密度降低,单位电导下降,而翻转电位及电压依赖特性未发生显著性改变。结论:腰4DRG神经元Ih的这些变化可能贡献于L5SNL大鼠的神经病理痛。

Abstract:

Objective: To investigate the changes of Ih and its channel,hyperpolarization-activated cyclic nucleotide gated cation channel(HCN),in the intact lumbar 4 DRG neurons following lumbar 5(L5) spinal nerve ligation(SNL).Methods: Rat neuropathic pain model was produced by tight ligation of L5 spinal nerve and Ih was recorded with whole-cell patch clamp technique.Results: The current density and the maximal conductance of Ih in the SNL group were decreased significantly compared with those in the sham-operation control,while the reversal potential and the channel biophysics properties of HCN channel did not show any significant change.Conclusion: These electrophysiological changes of Ih and HCN channel properties in the L4 intact DRG neurons might contribute to peripheral sensitization in L5 SNL neuropathic pain.