烟酰胺对帕金森病小鼠黑质细胞凋亡的影响

Effect of nicotinamide on neural apoptosis in substantia nigra of mice with Parkinson's disease

目的:探讨黑质细胞凋亡在帕金森病发病机制中的作用及烟酰胺对帕金森病小鼠黑质细胞凋亡和Bax蛋白表达的影响。方法:给C57BL小鼠腹腔注射1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)制备帕金森病小鼠模型。利用原位缺口末端标记法(TUNEL)及Bax免疫组化方法观察黑质细胞凋亡情况及烟酰胺干预的影响。结果:帕金森病小鼠黑质致密带可见大量凋亡细胞犤(19.43±3.33)个/视野犦Bax蛋白表达(Bax阳性细胞平均灰度值80.59±3.73)。预先应用烟酰胺能使凋亡细胞减少犤(6.33±2.35)个/视野犦,烟酰胺+MPTP组与MPTP组间比较差异有显著性意义(q=9.23,P<0.05)。预先应用烟酰胺也能使Bax蛋白表达降低(Bax阳性细胞平均灰度值107.59±2.50),烟酰胺+MPTP组与MPTP组间比较差异有显著性意义(q=7.44,P<0.05)。结论:烟酰胺可降低MPTP诱导的C57BL小鼠黑质细胞Bax蛋白表达,减少黑质细胞凋亡。

AIM: To investigate the role of apoptosis in the substantia nigra pars compact a(SNc)in the pathogenesis of Parkinson's disease(PD) and the effects of nicotina mide on cell apoptosis and Bax expression. METHODS:C57BL mice were injected with 1-methyl-4-phenyl -1,2,3,6-tetrahyd ropyridine(MPTP) intraperitoneally to establish PD models of rats. TDT-mediated dUTP biotin nick ending labeling(TUNEL) and Bax immunohistochemical method were made on the model rats to detect the SNc neuronal apoptosis as well as the effe ct of nicotinamide. RESULTS:There were many TUNEL positive nuclei[(19.43±3.33 )per visual field]a nd Bax protein expression(the gray scale value of Bax positive cells was 80.59± 3.73)in the SNc cytoplasm of PD mice.The TUNEL positive nuclei[(6.33±2.35) per visual field](q=9.23,P< 0.05) and Bax protein expression(the gray scale value of Bax positive cells was 107.59±2.50)(q=7.44,P< 0.05)were dramatically decreas ed by pretreatment of nicotinamide. CONCLUSION:Nicotinamide can lower Bax protein expression induced by MPTP and d ecrease neural apoptosis in SNc of PD mice.