鼠神经生长因子治疗大鼠坐骨神经损伤的疗效

Efficacy of mouse nerve growth factor in treating sciatic nerve injury in rats

目的探讨鼠神经生长因子治疗大鼠坐骨神经损伤的疗效。方法120只SD大鼠采用钳夹坐骨神经的方法构建大鼠单侧坐骨神经损伤模型,选取100只造模成功的SD大鼠随机均分为模型对照组、低剂量组、中剂量组、高剂量组和甲钴胺组。低剂量组、中剂量组、高剂量组分别肌肉注射鼠神经生长因子3、6、12μg/kg,每天给药1次;甲钴胺组给予甲钴胺注射液50μg/kg,每周给药3次;模型对照组给予0.9%氯化钠注射液,每天给药1次;五组给药连续4周。采用坐骨神经功能指数(SFI)、神经电生理检测、腓肠肌湿重及腓肠肌湿重恢复率分析大鼠坐骨神经恢复情况。采用免疫组化检测生长相关蛋白43(GAP-43)的表达。采用电镜观察并测量轴突直径和神经纤维髓鞘厚度。结果给药1、2、4周后,低剂量组、中剂量组、高剂量组和甲钴胺组SFI均优于模型对照组(P<0.01)。与模型对照组相比,给药4周后,中剂量组、高剂量组和甲钴胺组大鼠坐骨神经传导速度均提高(P<0.05),高剂量组和甲钴胺组腓肠肌湿重较重(P<0.05),低剂量组、中剂量组、高剂量组和甲钴胺组腓肠肌湿重恢复率较高(P<0.01),中剂量组、高剂量组和甲钴胺组轴突直径较大(P<0.01),低剂量组、中剂量组、高剂量组和甲钴胺组髓鞘厚度较厚(P<0.01)。与模型对照组比较,给药2周后,低剂量组、中剂量组、高剂量组和甲钴胺组GAP-43表达升高(P<0.05);给药4周后,中剂量组、高剂量组和甲钴胺组GAP-43表达降低(P<0.01)。结论鼠神经生长因子能促进大鼠坐骨神经损伤的恢复,提高坐骨神经传导速度,促进轴突生长发育。

Objective To investigate the efficacy of mouse nerve growth factor(NGF)in the treatment of sciatic nerve injury in rats.Methods The single side sciatic nerve injury models were established by clamping the sciatic nerve in 120 SD rats,in which 100 SD rats as the successful models were equally assigned into 5 groups and injected with mouse NGF 3μg/kg(group A),6μg/kg(group B)and 12μg/kg(group C)once a day,mecobalamine 50μg/kg(group D)three times a week,and 0.9%sodium chloride(group E)once a day as the model control.Five groups were treated for 4 weeks.The recovery of rat sciatic nerve was evaluated by sciatic nerve functional index(SFI),neuroelectrophysiological detection,wet weight of gastrocnemius and recovery rate of gastrocnemius wet weight.The expression of growth-associated protein 43(GAP-43)was detected by immunohistochemistry.The axonal diameter and thickness of the nerve fiber myelin were observed and detected by electric mirror.Results After treated for 1,2,and 4 weeks,the SFI was better in groups of A,B,C and D than that in group E(P<0.01).Compared to group E,the conduction velocity of sciatic nerve was quicker in groups of B,C and D,the wet weight of gastrocnemius was higher in groups of C and D,the recovery rate of gastrocnemius wet weight was higher in groups of A,B,C and D,the axonal diameter was bigger in groups of B,C and D and the thickness of the nerve fiber myelin was thicker in groups of A,B,C and D in 4 weeks after treatment(P<0.05 or P<0.01).Compared to group E,the expression of GAP-43 was higher in groups of A,B,C and D in 2 weeks after treatment and that was lower in groups of B,C and D in 4 weeks after treatment(P<0.05 or P<0.01).Conclusion The mouse NGF can promte the recovery of injuried sciatic nerve,improve the conduction velocity of the sciatic nerve and promote the growth and development of the axons.