【摘要】 目的:研究脑源性神经营养因子(BDNF)及其受体TrkB在大鼠大脑皮质时空分布变化。方法:进行免疫组织化学实验,观察BDNF及其受体TrkB在正常大鼠发育期、成年期和老龄期大脑皮质的定位分布及时间变化。结果:生后当天的大脑皮质,即有BDNF阳性神经元出现于Ⅴ层、Ⅵ层,以后Ⅵ层阳性细胞数量增加,Ⅱ~Ⅴ层也有表达。生后20~25d,各层阳性细胞数和染色强度均达高峰。成年后BDNF表达呈递减趋势。老年期,细胞形态发生明显的退行性变化。TrkB生后当天,主要分布于Ⅱ~Ⅴ层,以后逐渐增强。至成年期90d,阳性细胞数和染色强度达高峰。老年期,TrkB阳性细胞呈增龄性减少,Ⅴ层的阳性细胞排列不规则,体积缩小,轮廓僵直,边界不清。结论:大脑皮质BDNF及其受体TrkB的时空表达基本一致。表达高峰为生后20d。老龄期呈增龄性下降,细胞出现退行性变。更多还原

【Abstract】 Objective:To observe systematically the distribute of BDNF and TrkB in the normal rat neocortex during development phase and adulthood and aged phase.Methods: The expression changes of BDNF and TrkB in the normal rat neocortex during development phase and adulthood and aged phase were studied using methods of immunohistochemistry.Results: BDNF was expressed in the cortical layers Ⅴand Ⅵ in the group of postnatal day 0,reaching a peak between PND 20 and PND 25.The immunopositive substance decreased progressively during adulthood.The number of the immunopositive cells decreased remarkably during aged phase.The forms of immunopositive cell showed degeneration.TrkB was expressed in cortical layers Ⅱ~Ⅴ on PND 0.Afterward,immuostaining increased gradually.The immunopositive cell and immunostaining reached a peak during adulthood. TrkB immunopositvie cells decreased along with age-increasing.The form of the immunopositive cells showed degeneration.Conclusion: The expression of BDNF and TrkB reached a peak in neocortex of rats in the group of postnatal day 20.The expression of BDNF and TrkB decreased gradually after adulthood.During aged phase,the expression of BDNF and TrkB decreased significantly,and the form of the cell showed degeneration.更多还原