老龄大鼠脑组织不同部位VEGF的表达与微血管密度

目的：观察幼龄大鼠和老龄大鼠脑组织内不同部位VEGF 的表达及微血管密度(MVD)，探讨其在神 经系统衰老过程中的作用。方法：应用免疫组织化学对比观察3 月龄组和30 月龄组大鼠脑组织不同部位VEGF 的表达及MVD。结果：30 月龄组大鼠运动皮质区、海马CA1 区、海马CA3 区及第1 小脑小叶区VEGF 阳性细 胞个数及MVD 较3 月龄组对应区域明显减少，差异有统计学意义(P<0.01)；同组大鼠不同部位阳性细胞个数 均有明显变化(P<0.01)，其中运动皮质区表达最强，其次是海马CA3 区、海马CA1 区及第1 小脑小叶区。结论： 老龄大鼠脑组织各部位VEGF 及MVD 较幼龄大鼠明显减少，且不同部位VEGF 的表达及MVD 差异明显，其中 运动皮质区表达最强，提示补充外源性VEGF，可能可以促进脑组织内微血管的生成，延缓神经系统衰老。

Expression of vascular endothelial growth factor and microvessel density in different brain regions in aged rats

Objective: To observe the distribution of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in different brain regions in aged rats and determine the role of VEGF and MVD in the aging process of the nervous system. Methods: We observed the expression of VEGF and MVD in different parts of rat brain in the 3- month group and 30-month group with immunohistochemical technique. Results: Compared with the 3-month group, the 30-month group showed fewer VEGF-positive cells and MVD in the brain (P<0.01), and the number varied significantly in different brain regions (P<0.01). The motor cortex region contained more VEGF-positive cells and MVD than the hippocampus and cerebellum. Conclusion: VEGF-positive cells and MVD are decreased in every brain region of aged rats, and the motor cortex region contains more positive cells, suggesting exogenous VEGF may enhance the formation of microvessels and delay the aging of the nervous system.