周围神经减压术对糖尿病神经卡压大鼠细胞因子表达的影响

目的 探讨周围神经减压术对DPN大鼠模型脊髓背根神经节中细胞因子表达的影响.方法 50只SD大鼠以STZ诱导糖尿病模型.2周后,筛选造模成功的大鼠32只随机分为糖尿病对照组（DM组,n=8）、糖尿病神经卡压组（DPN组,n=12）及糖尿病神经卡压＋外周神经减压组（DPND组,n=12）.DM组不予任何干预,DPN及DPND组制作坐骨神经卡压模型.6周后,DPND组予神经减压术,DPN组予假神经减压手术.于神经卡压前后及减压手术前后不同时间（术前、术后2周、术后6周）分别以Von Frey单丝测定各组机械痛阈.术后6周,观察各组脊髓背根神经节病理,并通过酶联免疫法测定背根神经节中TNF-α、环氧酶2（COX-2）、VEGF及神经生长相关蛋白-43（GAP-43）的表达.结果 DPND组行神经减压术6周后机械痛阈较减压手术前及DPN组改善（P＜0.05）;脊髓背根神经节炎性反应及水肿现象轻于DPN组,且背根神经节中TNF-α及COX-2表达较DPN组降低,其中COX-2改变差异有统计学意义（P＜0.05）.DPND组VEGF及GAP-43的表达较DPN组有增高趋势,但差异无统计学意义. 结论 神经减压术可改善周围神经卡压造成的糖尿病大鼠机械痛阈升高现象,这可能与其调节脊髓背根神经节中相关细胞因子的表达有关.

Effects of nerve decompression on cytokines expression of diabetic peripheral neuropathy rats

Objective To explore effects of nerve decompression on cytokines expression on dorsal root ganglion of diabetic peripheral neuropathy （DPN） rat models. Methods Diabetic mellitus models were induced by streptozocin （STZ） in 50 SD rats. Two weeks later, 32 successfully induced diabetic rats were randomly assigned into diabetic mellitus group （DM, n=8）, diabetic peripheral neuropathy group （DPN, n= 12）, and diabetic peripheral neuropathy decompression group （DPND, n= 12）. Rats in DM group didn＇t receive any treatment. Rats in DPN and DPND groups were given sciatic compression operation. Six weeks later, rats in DPNP were given thorough nerve decompression operation, and rats in DPN were given pseudo nerve decompression operation. Mechanical threshold was measured using Von Frey filaments at different times before and after compression and decompression operation respectively （before, 2 weeks and 6 weeks after operation）. Six weeks later, pathological changes were observed, and cytokines expression, such as TNF-α, COX-2, VEGF, and GAP-43 in dorsal root ganglion of rats of all the three groups were detected by ELISA method. Results Mechanical threshold of DPND rats was improved after 6 weeks decompression operation than before operation in DPN group （P〈0. 05）. Sixweeks after decompression operation, phenomenon of inflammatory reaction and swelling were less in DPND group than in DPN group, TNF-α and COX-2 expression were less in DPND group than in DPN group, and decrease of TNF-α had statistical significance. VEGF and GAP-43 expression were increased in DPND group than in DPN group, but there were no statistical significance. Conclusion Peripheral nerve decompression can significantly improve high mechanical pain threshold induced by nerve compression, and this may have some relation with its regulative effect on expression of some cytokines in dorsal root ganglion.