坐骨神经损伤后脊髓前角细胞脑源性生长因子的表达及针刺治疗的作用

Changes of brain-derived neurotrophic factor expression after sciatic nerve injure and the effect of acupuncture

目的:探讨坐骨神经不完全性损伤后脊髓前角细胞脑源性神经生长因子(brain-derivedneurotrophicfactor,BDNF)表达水平变化及针刺对BD-NF表达的影响。方法:采用钳夹法制作大鼠左侧坐骨神经损伤模型,分为针刺组和对照组。用原位杂交、免疫组化技术检测相应节段脊髓前角细胞BDNF的表达水平,观察各组在1,7,4,21及28d的变化。用计算机图像自动处理系统进行定量分析研究。结果:对用原位杂交方法测得的坐骨神经损伤后大鼠脊髓前角BDNFmR-NA阳性细胞计数进行分析,组间和不同时间点比较差异均的非常显著性意义(P<0.01);计算用免疫组化方法测得的坐骨神经损伤后大鼠脊髓前角BDNFmRNA阳性神经元光密度值,组间和不同时间点比较差异均的非常显著性意义(P<0.01);坐骨神经损伤后损伤侧脊髓前角细胞中BD-NF表达水平在最初的3周内逐渐下降,然后开始恢复,但至第4周犤(45.38±1.56)个犦尚未恢复到健侧犤(62.88±1.23)个犦的水平。针刺组损伤侧脊髓前角细胞中BDNF表达水平除1,7d组外其余均高于对照组(P<0.01);而健侧BDNF表达水平在各时间点间相比较无明显差异。结论:在正常情况下,BDNF在脊髓前角细胞中能够表达。坐骨神经损伤后,BDNF的表达下降。针刺能促进损伤侧脊髓前角细胞中BDNF表达水平的增加;而对健侧BDNF表达水平无明?

AIM:To explore the changes of brain-derived neurotrophic factor(BDNF) express ion in spinal anterior horn after incomplete sciatic nerve injury and the effect of acupuncture on BDNF expression. METHODS:Left sciatic nerve model of injury was made by clipping on rats, and t hen model rats were divided into acupuncture and control groups.By the means of in situ hybridization and immunohistochemical staining, the expression level of BDNF was determined,and the changes of BDNF expression in the two groups were de tected on days 1,7,14,21 and 28.Analysis of figures was made quantitatively on c omputer with auto-disposal system. RESULTS:In situ hybridization test revealed that there were significant differ ences between the two groups and among different time points in BDNFmRNA positiv e cell counting of rat spinal anterior horn following sciatic nerve injury(P< 0. 01).Computer immunohistochemical staining showed that significant difference was also found between the two groups and among different time points in BDNFmRNA p ositive neuron absorbance of rat spinal anterior horn following sciatic nerve in jury(P< 0.01).After sciatic nerve injury,the level of BDNF expression trended to decrease in the first 3 weeks,and then began to increase,but did not increase t o the normal level of healthy side in the 4th weeks(45.38±1.56 vs 62.88±1.23). The level of BDNF expression was higher in the acupuncture group than the contro l group at different times points except at the 1st and 7th days(P< 0.01),while there was no significant difference among different time points. CONCLUSION:Under the usual conditions, BDNF can be expressed in spinal anterio r horn.After sciatic nerve injury,BDNF expression will be decreased.Acupuncture improves the level of BDNF expression in spinal anterior horn of injured sides, but it is ineffective for healthy sides.