黄喉鹀耳蜗核的传出投射

THE EFFERENT PROJECTIONS OF THE COCHLEAR NUCLEI IN EMBERIZA ELEGANS

用HRP顺行追踪方法,研究黄喉鵐(emberiza elegans)的两对耳蜗核,即角状核和巨细胞核的传出投射.将HRP注入角状核,在双侧上橄榄核,对侧外侧丘系核腹侧部,外侧丘系腹核及中脑背外侧核的背侧1/4的区域见到顺行标记纤维或终末.将HRP注入巨细胞核,标记纤维或终末分布于双侧层状核;标记细胞分布于同侧上橄榄核.结果表明:角状核投射至双侧上橄榄核,对侧外侧丘系核腹侧部,外侧丘系腹核及中脑背外侧核的背侧部.巨细胞核投射至双侧层状核.此外,巨细胞核接受同侧上橄榄核的传人,它可能是一条听觉的反馈回路.

The efferent projections of two cochlear nuclei-nucleus angularis and nucleus magnocellularis in emberiza elegans were investigated with anterograde HRP tracing methods.After HRP was injected into nucleus angularis,the anterogradely labeled fibers and terminals were observed in the bilateral superior olivary nucleus,as well as in the contralateral nuclei,including nucleus lemnisci lateralis pars ventralis,nucleus ventralis lemnisci lateralis and 1/4 dorsolateral area of nucleus mesencephalicus lateralis pars doralis.Injecting HRP into nucleus magnocellularis,the labelled fibers and terminals were found in the bilateral nucleus laminaris and the labeled neurons in the ipsilateral superior olivary nucleus.The results indicate that nucleus angularis projects to both superior olivary nucleus,contralateral nucleus lemnisci lateralis pars ventralis,nucleus ventralis lemnisci lateralis and the dorsolateral part of nucleus mesencephalicus lateralis pars doralis,and that nucleus magnocellularis projects to the bilateral nucleus laminaris.In addition,nucleus magnocellularis receives projections from the ipsilateral superior olivary nucleus,which may be an auditory feedback circuit.