GAD67-GFP基因敲入小鼠5-羟色胺与γ-氨基丁酸共存神经元在脑内的分布

Distribution of the co-localized serotonin neuron with GABA in the brain of GAD67-GFP knock in mouse

目的:采用免疫荧光组织染色方法,以GAD67-GFP基因敲入小鼠为实验动物,系统地观察了小鼠脑干内5-羟色胺(5-HT)与γ-氨基丁酸(GABA)的共存情况,为中枢神经系统内5-HT与GABA共存神经元的分布提供形态学证据。方法:应用免疫荧光组织染色技术,对GAD67-GFP基因敲入小鼠脑干内5-HT与GABA免疫荧光双重染色,观察双重标记神经元在5-HT细胞群(B1-B9)中的分布情况并计数。结果:在所有脑干的5-HT细胞群中,双重标记神经元在中缝大核区域内所占的比率最高,平均为10.0%,其次是中缝苍白核和中缝隐核,分别为1.8%和1.4%。中缝桥核与中缝背核所含的共存神经元比例小,仅0.9%和0.3%。而在其他细胞群即B4,B6和B8-9细胞组,未观察到双重标记神经元。结论:在中枢神经系统内,只有部分延髓中线核团的5-HT能神经元同时含有GABA,而中脑中线核团和脑干的其他非中线5-HT细胞群内未见这种共存神经元的存在。

Objective：To investigate the co-localization of the serotonin and GABA in the brainstem, providing the morphological evidence for the co-localization of serotonin （5-HT） and GABA in the central nervous system. Methods：5-HT and GABA in the brainstem of GAD67-GFP knock-in mouse were labeled by utilizing the double immunofluorescent histochemical staining. The colocalization of serotonin neuron with GABA was observed in the 5-HTergic B1-B9 cell groups and counted. Results：Of all the serotonin cell groups in the brainstem,the nucleus raphe magnus contained the most double-labeled cells with a mean of 10.0%, followed by the nucleus raphe pallidus and the nucleus raphe obscurus, with a mean of 1.8% and 1.4% respectively. Nucleus raphe pontine and nucleus raphe dorsal contained very few double-labeled cells with a mean of 0.9% and0.3%. No double-labeled neuron was found in B4, B6 and B8-9 cell groups at all. Conclusion：In the central nervous system, the co-localized serotonin neuron with GABA exists only in parts of the medullar raphe nucleus, but there is no this kind of neurons in the midbrain raphe nucleus and non- raphe serotonergic cell groups in the brainstem.