脑干神经元向前扣带回皮质中部区域的投射(英文)

Topography of the afferents to middle portion of the cingulate cortex from brainstem

目的：用逆行标记方法观察脑干神经元向皮质扣带回中部（the middle portion of the cingulate cortex,MCC）的纤维投射。方法：立体定位注射法将0.06-0.08μl的4%荧光金（Fluoro-gold,FG）注射至MCC（Bregmma：＋0.2,-0.3,-0.8 mm）部位,7 d后处死大鼠,含4%多聚甲醛的磷酸缓冲液（PB）灌注固定,取脑组织,制作30μm厚度的冰冻切片,荧光显微镜下观察FG逆行标记神经元的定位分布并计数。结果：MCC与皮质间有广泛的联系,包括与同侧、对侧和扣带回内部的联系。在脑干中缝核簇、蓝斑、被盖腹侧区、被盖背内侧区及中脑中央灰质（α部）均可观察到FG逆标神经元的分布,以上FG标记神经元以同侧为主,对侧较少。结论：以上核团向MCC的投射表明MCC接受来自脑干神经元的广泛投射,提示MCC神经元的活动受到脑干众多结构的调控。

Objective：The afferents from brain stem to the middle portion of the cingulate cortex（ MCC） in the present study were investigated by using retrograde tracing technique.Methods：A volume of 0.06 - 0.08 μl 4% Fluoro-gold（ FG） was injected into MCC（ Bregmma：＋ 0.2,-0.3,-0.8 mm） by using a stereotaxic apparatus.The rats were euthanized,perfused with 4% paraformaldehyde in phosphate buffer（ PB） at the 7th days after injection.Rat brains were sectioned in the coronal planes at 30 μm.FG retrogradely labeled neurons were examined using fluorescence microscope.Results：The present results have demonstrated that there were extensive MCC-cortical connections,including ipsilateral,contralateral and intracingulate connectivity.The distribution of FG-labeled neurons in the brain stem including raphe nuclei,locus coeruleus,ventral tegmental area,dorsomedial tegmental area and midbrain central gray（ alpha part） were frequently observed.These FG-labeled neurons were mainly ipsilateral dominance and less in contralateral.Conclusion：The topographic afferents to the MCC indicates that MCC receives widespread projections from brainstem,suggesting that neuronal activities in the MCC are extensively modulated by diverse brain stem structures.