加巴喷丁对SNL模型大鼠损伤DRG神经元细胞内[Ca^2＋]i的影响

Effects of gabapentin on free calcium concentration of injury dorsal root ganglion neurons in spinal nerve ligation rats

目的：探讨加巴喷丁对脊神经结扎（SNL）模型大鼠损伤背根神经节神经元胞内游离钙浓度的影响。方法：SD大鼠,雄性35只,4~6周龄,采用左侧L5 SNL术制备大鼠神经病理性疼痛模型。于结扎后15 d采用酶消化法急性分离损伤同侧L5背根神经节神经元（SNL组）和假手术组L5背根神经节神经元（Sham组）。采用流式细胞仪检测10、100和300μmol/L浓度加巴喷丁对损伤侧L5背根神经节神经元基础及高K＋激发胞内游离钙浓度的影响。结果：加巴喷丁剂量依赖性地抑制高钾激发的胞内游离钙浓度的增加（P〈0.05或P〈0.01）,但对静息钙无作用。结论：加巴喷丁对神经病理性疼痛大鼠损伤背根神经节神经元高钾激发的钙内流的抑制作用,可能与其抗伤害作用的外周机制相关。

Objective：To investigate the effects of gabapentin（GBP） on free calcium concentration [Ca2＋]i of injury DRG in an experimental rat model with neuropathic pain following spinal nerve ligation. Methods：Thirty five male SD rats aged 4~6 weeks were used in this study. Left L5 spinal nerve was ligated between DRG and sciatic nerve and cut distal to the ligature to reproduce neuropathic pain model. On the 15th postoperative day,these animals were decapitated. L5 DRGs were isolated and the neurons in the ganglion were enzymatically dissociated in SNL group and Sham group. Flow cytometer was used to monitored the resting [Ca2＋]i and high K＋（50 mmol / L）-evoked[Ca2＋]iwith or without GBP in L5 DRG. Results：GBP attenuated high K＋（50 mM）-evoked[Ca2＋]iin a dose-dependent manner（P 0.05 or P 0.01）,but no effect on resting [Ca2＋]i. Conclusion：GBP significantly inhibited high K＋-evoked [Ca2＋]iin injured DRG neurons in neuropathic pain rats,which may be a peripheral way of GBP which involved in the antinociception mechanism.