目的:观察生长和分化因子10(GDF10)在神经病理性疼痛大鼠脊髓中的表达变化.方法:取雄性SD大鼠60只,通过结扎左侧L5脊神经制备神经病理性疼痛模型,于术前1 d,术后当天及术后1 d、3 d、10 d、21 d检测大鼠左后爪50%缩爪阈值,并采用免疫荧光染色及Western blot检测大鼠L5脊髓后角GDF10的表达变化.结果:脊神经结扎大鼠在术后1 d缩爪阈值开始降低,自3 d起,与正常对照组相比差异有统计学意义(P〈0.05),到10 d阈值下降最明显,至21 d呈现持平状态.免疫荧光检测观察到伤侧L5脊髓组织中GDF10主要表达于脊髓背角神经元细胞的胞浆内.GDF10在术后持续降低,到10 d降低最为显著,与正常组相比差异具有统计学意义(P〈0.05),一直持续低水平表达至21 d.Western blot证实术后10 d脊髓中GDF10蛋白的表达较正常组大鼠明显降低(P〈0.05).结论:大鼠脊神经结扎使脊髓背角中GDF10表达减少,其减少可能与大鼠脊神经损伤后对机械刺激引起的疼痛过敏有关联.
AIM: To observe the expression change of growth and differentiation factor 10 ( GDF10 ) in the spinal cord of the rats with neuropathic pain .METHODS:Male SD rats (n=60) were used.The neuropathic pain was induced by ligation of left L 5 spinal nerves of the animals .The paw withdrawal threshold was detected 1 d before surgery , and 0 d, 1 d, 3 d, 10 d and 21 d after surgery.The changes of GDF10 in the dorsal horn of L5 spinal cord were detected by immunofluorescence staining and Western blot .RESULTS:The paw withdrawal threshold of the rats with spinal nerve ligation was decreased from 1 d after surgery until 3 d with obvious difference compared with the na ve rats ( P〈0.05 ) , continuously decreased until 10 d, and then stabilized at 21 d.The GDF10 was located in the cytoplasm of the neurons in the dorsal horn of L5 spinal cord detected by immunofluorescence staining .The expression of GDF10 in L5 dorsal horn de-tected by immunofluorescence staining was reduced after surgery , significantly decreased from 10 d ( P〈0.05) until more than 21 d after surgery in spinal nerve ligation group compared with na ve group.GDF10 in L5 spinal cord detected at 10 d after surgery by Western blot was significantly down-regulated in spinal nerve ligation group compared with na ve group (P〈0.05).CONCLUSION:Spinal nerve ligation induces the decrease in GDF 10 expression in spinal dorsal horn .The down-regulation of GDF10 may contribute to the regulation of hyperpathia caused by mechanical stimulation after the injury of spinal nerve .