鸣禽中脑听觉核团边缘区神经投射的研究(英文)

Projection pathways in the margin of auditory nuclei in the songbird mesencephalon

对鸣禽白腰文鸟 ( Lonchura striata)中脑听觉核团——背外侧核 ( nucleus mesencephalicus lateralis,pars dorsalis,MLd)和丘间核 ( nucleus intercollicularis,ICo)的脑啡肽免疫化学特性和神经联系进行了研究。结果发现 :脑啡肽能标记纤维或细胞主要分布于中脑听觉核团的背外侧核边缘区、丘间核 ,而背外侧核中央区几乎无分布。双向神经示踪剂生物素结合的葡聚糖胺注射入 MLd边缘区后 ,从端脑到延髓的许多核团或脑区均获得了传出传入神经标记。 MLd边缘区接受 5个核团或脑区的投射 ,即 :端脑古纹状体粗核( robust archistriatum,RA)壳区、下丘脑视前核 ( nucleus preopticus anterior,POA)、脑桥臂旁核 ( nucleusparabrachialis ventrolateralis,PBvl)、延髓下橄榄上核 ( nucleus infraolivaris superior,IOS)和延髓喙腹外侧核 ( nucleus rostral ventrolateral medulla,RVL) ;而 MLd边缘区发出纤维 ,支配间脑卵圆核 ( nucleusovoidalis,Ov)壳区和外侧下丘脑 ( nucleus lateralis hypothalami,LHy)。结果提示鸣禽中脑背外侧核边缘区在听觉发声、内分泌活动及其他生理活动的联系中可能具有重要作用。

The mesencephalic auditory nuclei,the nucleus mesencephalicus lateralis,pars dorsalis (MLd) and nucleus intercollicularis (ICo),were investigated in the adult songbird ( Lonchura striata ) for met enkaphalin (ENK) immunoreactivity and neuronal connectivity. It was found that the ENK labeled fibers and neurons were distributed in the MLd margin and ICo, but were nearly absent in the central MLd. After a neural tracer biotionylated dextran amine (BDA) was injected into the MLd margin, the labeled fibers and neurons were found in the brain nuclei or areas from telencephalon to medulla. There were five nuclei or areas project to MLd margin:the cup of n. robustus archistriatalis (RA) of telencephalon, the n. preopticus anterior (POA) of hypothalamus, the n. parabrachialis ventrolateralis (PBv1) of pons ,the n. rostral ventrolateral medulla (RVL) and the n.infraolivaris superior (IOS) of medulla. The MLd margin projected to two diencephalic areas, the shell of n. ovoidalis (Ov shell) and the lateral hypothalamus (LHy). The projections from MLd margin to PBv1 and hypothalamus suggest that the MLd margin in the songbird may play an important role in the integration of anditory vocalization, endocrine and other physiological activities.