老龄大鼠脑组织不同部位HIF-1α的表达规律探讨

Expression of hypoxia inducible factor-1α in different brain regions in aged rats

目的观察低氧诱导因子-1α(HIF-1α)在老龄大鼠脑组织不同部位的表达规律,探讨HIF-1α在神经系统衰老过程中的作用。方法应用尼氏染色和免疫组化技术对比观察3月龄和30月龄大鼠脑组织不同部位神经细胞内尼氏体及HIF-1α的表达情况。结果30月龄大鼠脑组织各部位神经细胞体积大,排列稀疏,胞浆内尼氏体稀疏。与3月龄组比较,30月龄组大鼠脑组织内各部位阳性表达细胞数目明显增多(P<0.01),且各部位阳性细胞个数有显著变化(P<0.01),其中海马CA3区阳性细胞数最多,而运动皮质区及第1小脑小叶阳性细胞数相对较少。结论老龄大鼠脑组织各部位神经细胞蛋白质合成功能减弱,而HIF-1α表达增强,其中又以海马区表达最强,推测HIF-1α可能在衰老过程中尤其是记忆减退方面发挥重要作用。

Objective To observe the distribution ofhypoxia inducible factor-1α （HIF-1α） in different brain regions in aged rats and investigate the role of HIF-1α in the aging process of the nervous system. Methods The Nissl bodies and HIF-1α expression in different brain regions were observed in rats aged 3 and 30 months using Nissl staining and immunohistochemical method, respectively. Results In the 30-month-old rats, the neural cells in 4 different brain regions presented with large cell body and loose alignment, containing reduced Nissl bodies in the cytoplasm. Compared with the 3-month-old rats, the aged rats showed greater number of HIF-1α-positive cells in the brain （P〈0.01）, and the number varied significantly between the different brain regions （P〈0.01）. The CA3 region contained the greatest number of positive cells, which were fewer in the motor cortex and cerebellum, Conclusion The capacity for protein synthesis in the neural cells is weakened but the expression of HIF-1α increased in aged rats, suggesting the important role that HIF-1α may play in the aging process of the nervous system, especially in hypomnesis.