糖尿病痛性周围神经病变大鼠脊髓小胶质细胞Toll样受体3的变化

摘要

目的:观察糖尿病痛性周围神经病变大鼠脊髓小胶质细胞Toll样受体3(TLR3)的变化.方法:雄性SD大鼠,采用腹腔注射链尿佐菌素(STZ)制备糖尿病痛性周围神经病变模型.取造模成功的大鼠10只作为糖尿病组(D组),取10只同月龄腹腔注射0.9%氯化钠液大鼠为对照组( C组).观测2组大鼠的血糖水平和行为学评分,并应用免疫荧光双标记和激光共聚焦显微镜技术比较各组脊髓背角TLR3的变化.结果:与C组比,D组血糖在注射STZ 2d后显著升高;在注射STZ后14～28 d 机械缩足阈值(mechanical withdrawal threshold,MWT)降低; 注射STZ 后28 d,D组TLR3表达显著上调并且主要与小胶质细胞共标.结论:小胶质细胞TLR3可能参与了糖尿病周围神经痛的发生.%Objective:To observe change of Toil-like receptor (TLR3) in microglia in spinal cord of rats with diabetic neuropathy.Mail SD rats were divided into 2 groups (n= 10,each): diabetes mellitus group(Group D) and control group(Group C). Methods:Diabetes mellitus was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg and confirmed by blood glucose level＞ 16. 7 mmol/L.Control group was induced by intraperitoneal saline. The blood glucose level and the behavior score of rats were recorded. The expression of TLR3 was observed in microglia in spinal cord through immunofluorescence double staining and laser scanning confocal microscopy technique. Results: The blood glocose level in Group D was significantly increased after intraperitoneal STZ injection 2d as compared with Group C. The mechanical withdrawal threshold was significantly decreased after intraperitoneal STZ at 14-28d as compared with the baseline in Group D and was significantly lower than that in Group C. Immunofluorescence demonstrated that the expression of TLR3 in the dorsal horn was significantly up-regulated and mainly in microglia after STZ injection in Group D. Conclusions: TLR3 of microglia are possibly involved in the pathogenesis of diabetic neuropathic pain.