雌性白腰文鸟发声调控核团的神经联系

THE NEURAL CONNECTIONS AMONG VOCAL CONTROL NUCLEI IN THE FEMALE BENUGALSE FINCH (LONCHURA STRIATA SWINGOEI)

应用免疫组织化学和神经示踪方法 ,对脑啡肽在雌雄鸣禽白腰文鸟脑中发声调控核团中的分布差异 ,以及雌性白腰文鸟发声调控核团—古纹状体栎核的神经联系进行了研究。结果发现 :(1)雌雄白腰文鸟端脑发声调控核团上纹状体腹尾侧核、古纹状体栎核中存在脑啡肽能纤维分布 ,但脑啡肽能纤维在雄性的此二核内分布比较集中。在端脑的其它发声调控核团内 ,仅新纹状体前部外侧巨核有少量脑啡肽能细胞。在中脑及以下水平 ,脑啡肽分布在雌雄间无差别。 (2 )雌鸟古纹状体栎核和上纹状体腹尾侧核与中脑背内侧核之间仅存在弥散且较弱的神经联系 ,而与学习记忆相关的核团—新纹状体前部外侧巨核有较强的神经联系。(3 )中脑背内侧核与脑桥臂旁核、延髓上橄榄下核、延髓喙腹外侧核、舌下神经核气管鸣管部存在广泛联系 ,雌雄间未见差别。

The distribution of Met enkephalin in the vocal control nuclei of male and female songbird, benugalse finch (Lonchura striata swingoei)was studied by use of immunohistochemistry. The neural connections of RA (the robust nucleus of the archistriatum) and its connected nuclei were then investigated by employment of a neural tract tracer, biotinylated dextran amine (BDA) in the female benugalse finch. The results were as follows: (1)There were enkephalin positive fibers in the male or female HVC (the caudal nucleus of ventral hyperstriatum) and RA, but there were also some enkephalin positive cells in the male RA. There were not any other enkephalin positive region in the other vocal control nuclei in the telencephalon except that there were few enkephalinergic cells in the lMAN (lateral magnocellular nucleus of anterior neostriatum). There were not any sexual differences of Met enkephalin distribution in the vocal control nuclei in the midbrain, pons and medulla. (2) There were only diffuse or sparse neural connections between RA and the two other vocal control nuclei: HVC and DM (dorsomedial nucleus) in the female, compared to the RA in the male reported previously. However, there were more dense connections between RA and lMAN, a nucleus which was involved in the vocal learning, than connections between RA and HVC. (3) There were no differences in the connection of DM between female and males in the songbird. It was revealed that DM was connected with PBvl(nucleus parabrachilis ventrolateralis), IOS(nucleus infraolivaris superior), RVL(nucleus of the rostral ventrolateral medulla)and nXIIts (the tracheosyringeal portion of the hypoglossal nucleus) in the female. This study provided neural basis for singing behaviors, such as, vocal perception, coupling and discrimination between males and females. (Figure 3 on plate 28)