Electrophysiological properties in dorsal root ganglion neurons in lumbar radiculopathy model

在本研究中，我们建立了一个大鼠模型与收缩的近端网站的DRG。采用全细胞膜片钳技术，对腰神经根病大鼠模型和假手术大鼠DRG神经元的动作电位和Na^+-> K^+电流特性进行了比较，结果表明，腰神经根缩窄组大鼠的触觉敏感性和热敏感性均显著高于假手术组和对照组。在动作电位的测量中，发现神经根收缩组的神经元的阈值电流、静息膜电位、后超极化和APD 50均发生显著变化。DRG神经元的兴奋性也通过检查响应于长时间电流注入的放电模式来评价。持续爆发的发生率显着高于在假手术神经元的根缩神经元。在膜电流的测量中，根缩神经元的Na^+电流明显大于假手术神经元。K^+电流密度和电压依赖性无显著差异。缩根后DRG兴奋性增加可能是Na^+通道的范围或可用性增加的结果。腰神经根性疼痛可能是由Na^+通道表达和电流特性的这些变化引起的。

In the present study, we established a rat model with constriction of the proximal site of the DRG. The action potential and Na^<+-> K^+ current properties of DRG neurons in the rat model of lumbar radiculopathy are compared with sham-operated rats through the use of whole-cell patch clamp recordings.The rats in the root constriction group demonstrated statistically significant increase in tactile sensitivity, and higher thermal sensitivity than those in the sham operated and control groups up to 28 days after surgery. In measurement of the action potential in DRG neurons, significant changes were found in the threshold current, resting membrane potential, afterhyperpolarization, and APD50 of the neurons from the root constriction group. Excitability of DRG neurons was also evaluated by examining the discharge patterns in response to prolonged current injection. The incidence of sustained burst was significantly higher in root constriction neurons than in sham-operated neurons. In measurement of the membrane current, the Na^+ current in root constriction neurons was markedly larger than that in sham-operated neurons. There were no significant differences in K^+ current density and voltage dependency. Increased DRG excitability after root constriction could be a result of an increase in either the extent or available of Na^+ channels. Lumbar radicular pain may be caused by these changes in, Na^+ channel expression, and current properties.