黄雀(Carduelis spinus)上橄榄核的传入性联系—HRP顺逆行追踪法研究

分别将HRP微电泳入黄雀的上橄榄核(SO)、角状核、层状核和巨细胞核,观察其顺、逆行标记物的分布.结果表明,SO接受同侧层状标和双侧角状核的传入,双侧SO之间有交互投射,SO的纤维投射至外侧丘系核腹侧部、外侧丘系腹核和中脑背外侧核.因此,它属于听觉传入通路中的第二级中继站.此外,SO向巨细胞核投射并形成巨细胞核→层状核→SO→巨细胞核的闭合环路.此环路可能参与听觉信息的反馈及声源定向等的初步整合机能.

The Afferent Connections of the Superior Olivary Nucleus in Carduelis spinus-A HRP Anterograde and Retrograde Tracing Study

The afferent projections of superior olivary superior (SO) in Carduelis spinus have been investigated by using anterograde and retrograde HRP tracking techniques. After HRP was iontohoreticall delivered into the SO, retrogradely labelled neurons were observed in the bilateral nucleus angularis (NA) and the ipsilateral nucleus laminaris (NL), anterogradely labelled fibers and terminals were concentrated in the ipsilateral nucleus magnocellularis (NM), and the contralateral nucleus lemnisci lateralis, pars ven tralis (LLv), nucleus ventralis lemnisci lateralis (VLV) and dorsolaterally of nucleus mesencephalicus lateralis, pars dorsalis (MLd). And there are some retrogradely labeled neurous and anterograde labeled terminals in the contralateral SO. In addition, after injecting HRP into the NL and the NA respectively, anterogradely labeled fibers and terminals were found in the SO. After injecting HRP into the NM, retrogradely labeled neurous were observod in the SO. The results indicate that the SO receives projections from the ipsilateral NL and from the bilateral NA. There are some reciprocal projections between the left and right SO. The SO projects to the LLv, to the VLV, and to the MLd, The results indicate that the SO is the secoud neuron relay station of the auditory pathway in brain. Besides, the SO projects to the NM and forms the close circuit of NM-to-NL-to-SO-to-NM. The results suggest that the neural circuit may be involved in the integration functions of audition and sound loclization.