大鼠缰核的细胞分区及其至边缘中脑区的投射

THE SUBDIVISIONS OF THE HABENULAR NUCLEUS AND THEIR TOPOGRAPHIC PROJECTIONS TO THE LIMBIC MID-BRAiN AREA

用Nissl和Weil染色法以及HRP和荧光素逆行追踪技术,研究了大鼠缰核的细胞分区及其至边缘中脑区的投射。结果表明:大鼠的外侧缰核可分内侧区、外侧区和中间区,其中包括四个亚核,即内侧亚核、外侧亚核、背侧亚核和腹侧亚核。将追踪物分别输入脚间核、中央上核、中缝背核、脑桥嘴侧网状核或被盖腹侧区,观察到内侧缰核至脚间核的投射存在局部定位关系。中央上核主要接受背侧亚核和腹侧亚核的传出投射;中缝背核主要接受内侧亚核的传出投射;脑桥嘴侧网状核主要接受外侧亚核的传出投射。中央上核、中缝背核、脑桥嘴侧网状核和被盖腹侧区也接受内侧缰核腹外侧区细胞的传出投射。研究结果提示缰核至边缘中脑区不同核群的投射存在分区联系。

The Wistar rats were studied by using Nissl,Weil stain and HRP or fluorecence tracing methods to investigate the subdivisions of the habenular nucleus and their topographic projections to the limbie mid-brain area.The results were as follows:(1)According to the features of the neurons and their fiber connections,the lateral habenular nucleus(LHb)could be subdivided into four subnuclei:the medial subnucleus(m-LHb),the lateral subnucleus(1-LHb),the dorsal subnucleus(d-LHb)and the ventral subnucleus(v-LHb).(2)After injection of HRP or fluorescent substance into the interpeduncular nucleus(IP),the central superior nucleus(CS),the dorsal raphe nucleus(DR),the reticular pontis oralis nucleus(RPO)and the ventral tegmental area(VTA),the projections of the habenular subnuclei to the limbic mid-brain area were found to be topographically localized.The dorsomedial area of the medial habenular nucleus(MHb)projected mainly to the ventral part of the IP,while the ventrolateral area of the MHb to the dorsal part of the IP.The CS received mainly fibers from both the d-LHb and v-LHb.The DR received mainly fibers from the m-LHb.Most of the fibers projecting to the RPO came from the 1-LHb.And the VTA received sparse fibers from all subnuclei of the LHb.