【摘要】 目的观察糖尿病早期大鼠脊髓背角及背根神经节神经生长因子(NGF)的表达及其与疼痛行为的相关性。方法50只SD大鼠随机分为制模组(DM组,n=40)和正常对照组(C组,n=10)。DM组又均分为制模1周组(DM1组)、制模2周组(DM2组)、制模4周组(DM4组)和制模8周组(DM8组)四个亚组。按55mg/kg一次性腹腔注射链脲佐菌素(STZ)建立糖尿病大鼠模型。在制模前及制模后1、2、4、8周利用vonFreyhairs测定大鼠机械痛阈,并通过蛋白质免疫印迹法测定每个时间点大鼠脊髓背角和背根神经节NGF的表达水平。结果糖尿病大鼠机械痛阈在制模1周后即明显下降,并持续至8周;分别在制模2周和1周后脊髓背角和背根神经节内NGF表达水平出现显著下调,并分别持续至4周和8周。大鼠NGF表达水平与机械痛阈存在正相关性。结论糖尿病早期大鼠外周及中枢神经系统NGF表达即出现下调,并与疼痛相关。更多还原

【Abstract】 Objective To observe the dynamic expression of nerve growth factor (NGF) in spinal dorsal horn and dorsal root ganglion (DRG) of diabetic rats and its correlation with mechanical threshold. Methods Fifty male SD rats were randomly divided into diabetic model group(DM,40 rats) and control group(C,10 rats).DM group was divided into 4 subgroups of DM1,DM2,DM4 and DM8 with 10 rats each. The diabetic model was established by a single intraperitoneal injection of streptozocin (STZ 55mg/kg).Mechanical threshold was assessed using von Frey hairs before and on the 1st week(DM1),2nd week(DM2),4th week(DM4) and 8th week(DM8) after the formation of diabetes model. The NGF expression in spinal dorsal horn and DRG was measured by Western blot at the same time points. Results The mechanical threshold was decreased 1 week after the formation of diabetes model,which lasted for 8 weeks.The NGF expression was reduced in 2 weeks,which lasted for 8 weeks in spinal dorsal horn,and for 4 weeks in the DRG.The NGF protein level was positively correlated with mechanical threshold. Conclusion The NGF expression in peripheral and central nervous system was decreased in the early period of diabetes model and it is correlated with pain.更多还原