微波对坐骨神经损伤大鼠脊髓内生长相关蛋白-43表达的影响

摘要

目的:观察微波对坐骨神经损伤大鼠脊髓内生长相关蛋白-43(GAP-43)表达的影响,探讨微波促进周围神经再生的作用机制.方法:选取成年雄性SD大鼠64只,制成右侧坐骨神经钳夹损伤模型,随机分为微波治疗组和非治疗对照组,各32只,每组又分为3d、7d、14d、28d四个时间段各8只.治疗组于造模24h后取俯卧位,双腿伸直固定于实验台上,采用2450MHz微波辐射治疗,输出功率为6W,6min欣,5次/周,休息2d,直到取材的前一天.对照组于治疗组治疗同时予6min空白对照.于相应时间行大鼠一般状态观察,坐骨神经功能指数(SFI)测定及免疫组化染色观察GAP-43的表达.结果:微波治疗组术后大鼠一般状态优于对照组,治疗组SFI指数在术后第14天即出现明显升高,对照组则在术后第21天才开始明显升高,并且术后第14、21、28天治疗组SFI指数明显高于对照组(P＜0.01),免疫组化染色示坐骨神经损伤后脊髓内GAP-43表达增强,在术后第3、7、14天治疗组GAP-43明显高于对照组(P＜0.05,P＜0.01).结论:周围神经损伤后早期应用微波辐射治疗能增加GAP-43的表达,促进损伤神经再生及功能恢复.%Objective: To investigate the effect of microwave on expression of growth associated protein-43(GAP-43) in spinal cord after sciatic nerve injury of rats, and to explore the mechanism of microwave promoting regeneration of peripheral nerves.Method: Sixty-four male adult SD rats were used to establish forceps crushed models on right sciatic nerve, and randomly divided into two groups: microwave treated groups (n=32) and operative control groups(n=32). Each group was divided into 3d(n=8), 7d(n=8), 14d(n=8) and 28d(n=8) postoperation groups. Then the rats of microwave treated group were fixed on a table prostrated and the injured part were exposed to 2450MHz microwave at 6W for 6min each time, 5d each week from the 1st d after operation to Id before to be sampled. The rats of control group were also fixed on a table prostrated at the same time, but without microwave exposure. The general state of rats were observed, the sciatic functional index(SFI) was analyzed and immunohistochemistry staining techniques were used for the detection of GAP-43.Result: The general state in microwave treated group were better than that in control group. The SFI index in microwave treated group rose obviously on the 14th d postoperation, while in control group rose on the 21th d postoperation. The SFI indexes on the 14tlu 21th and 28th d postoperation in microwave treated group were significantly higher than those in control group (P<0.01). The immunohistochemical staining showed that GAP-43 pro-tein expression in spinal cord increased after sciatic nerve injury,and on the 3th,7th and 14th d postoperation in microwave treated group GAP-43 increased significantly compared with those in control group (P<0.05 ,P<0.01). Conclusion:Microwave could enhance the expression of GAP-43 and promote the regeneration and function recovery of injured peripheral nerve after early microwave irradiation.Author's address The Second Affiliated Hospital, Dalian Medical Iniversity, Dalian, 116027