脑源性神经营养因子在大鼠海马CA3区发育过程中的表达

采用免疫组织化学ＡＢＣ 法，研究脑源性神经营养因子在大鼠海马ＣＡ３ 区发育过程中的表达，观察其免疫反应产物的分布。结果表明：脑源性神经营养因子阳性物质在生后零天（Ｐ０）组位于ＣＡ３ 区细胞周围间质内；Ｐ１０，Ｐ１５ 和Ｐ２０ 组脑源性神经营养因子免疫反应产物位于锥体细胞内，幅射层内可见阳性苔藓纤维终末，这些终末随生后日龄增加而增加。Ｐ３０ 组脑源性神经营养因子免疫反应产物仅见于细胞周围间质内，未见细胞胞浆内有阳性物质分布，但偶见脑源性神经营养因子阳性细胞核位于ＣＡ３ 区锥体细胞层，辐射层内有较多的苔藓纤维阳性终末。本研究结果提示，发育早期大鼠海马ＣＡ３ 区脑源性神经营养因子分布于细胞周围间质而生后１０ 至２０ 天发育期间，ＣＡ３ 区锥体细胞合成脑源性神经营养因子并可沿神经元轴突顺行运输、传递信息。

THE EXPRESSION OF BRAIN DERIVED NEUROTROPHIC FACTOR IN DEVELOPING HIPPOCAMPAL CA3 OF RAT

The expression of brain derived neurotrophic factor(BDNF)in development of rat was studied immunohistochemically in hippocampus(CA3). It was demonstrated that BDNF immuno positive substance was distributed in extracellular matrix in group of postnatal day 0(P0). BDNF immunoreactive neurons appeared in cells of pyramidal cell layer in P10, P15 and P20. Thus, there also was more BDNF expressed in the mossy fiber endings in the radiation layer of CA3, and they were increasing along with the postnatal age. In P30, BDNF immunoreactive positive substance was only noted in the extracellular matrix, but was not defined, however, in the cytoplasm, whereas BDNF immunoreactive nucleus could occasionally be found in pyramidal cells of CA3. There were a lot of BDNF immunoreactive mossy fiber endings in the radiation layer. Our data suggest that BDNF was distributed in CA3 extracellular matrix during early days of development. And on the other hand, BDNF was synthesized in CA3 pyramidal cells during P10～P20, and played an important role in transmitting messages along the neuroaxons of anterogradely.