新生鼠大脑皮质和中脑多巴胺神经元原代培养中NGF诱导c-jun　mRNA表达的研究

A STUDY OF C-JUN mRNA EXPRESSION OF CORTICAL AND MESENCEPHALIC DOPAMINERGIC NEURONS INDUCED BY NGF FROM POSTNATAL RATS

用神经生长因子（nervegrowthfactor，NGF）分别处理原代培养的新生大鼠大脑皮质和中脑腹侧部神经元，应用免疫组织化学和原位杂交双重标记方法，观察不同时间NGF处理的神经元表达原癌基因c－junmRNA的情况。结果发现，神经特异性烯醇化酶（neuronspecificenolase，NSE）阳性的大脑皮层神经细胞在NGF处理15分钟即可表达c－junmRNA，2小时达高峰，4小时后开始下降，到8小时后基本消失．未经NGF处理的大鼠大脑皮层神经细胞不表达c－junmRNA；酪氨酸羟化酶（tyrosinehydroxylase，TH）阳性的中脑多巴胺能（Dopaminergic，DA）神经元经NGF处理也不表达c－jun基因。提示NGF与其受体结合可以激活神经细胞快速，短暂的一过性表达c-jun基因，作为第三信使，调节从细胞质膜到核的信号传递，同时也间接证明了新生大鼠大脑皮层神经细胞膜上存在神经生长因子受体（nervegrowthfactorreceptor，NGFR），而中脑DA神经细胞对NGF无应答反应。

Using double labeling method of in situ hybridization and immunocytochemistry, the expression of pro-oncogene c-jun of neurons stimulated by NGF in various time was observed.The results showed that the c-jun mRNA expression of the conical neurons which were neuron specific enolase (NSE) positive started in 15 minutes after NGF stimulation, peaked at 2 hours, declined at 4 hours and disappeared at 8 hours. The cortical neurons without the stimulation of NGF did not express the c-jun gene. This indicated that NGF combined with its receptors could activate the neurons to express the c-jun gene rapidly. As a third message, it regulated the signal transmission from the membrane of cytoplasm to nuclei. NGFR existed in the memrane of the conical neurons of neonatal rats. However, mesencephalic DA neurons did not respond to NGF.