鸽中脑半圆隆枕传出投射的研究

应用ＰＨＡ－Ｌ和Ｂｉｏｃｙｔｉｎ两种神经示踪物对非鸣禽环鸽（Ｓｔｒｅｐｔｏｐｅｌｉａｒｉｓｏｒｉａ）中脑半圆隆枕（ｔｏｒｕｓｓｅｍｉｃｉｒｃｕｌａｒｉｓ）的传出投射进行了分区研究。结果发现半圆隆枕丘间核内缘（ＩＣＭ）发出两束纤维分别向尾端投射至外侧丘系背核腹侧（ＬＬＤｖ）周围和向首端投射至丘脑卵形壳（Ｏｖ－ｓｈｅｌｌ）；丘间核（ＩＣｏ）发出的纤维直接投射至下丘脑前内侧核（ＡＭ）。从脑桥至听丘各级听神经核周围，均存在疏松网状神经纤维结构区，它们相互连接形成了一条与经典听觉神经通路相平行的旁听觉神经通路。这是首次关于鸟类发声、听觉和内分泌三维系统存在直接神经环路联系的较为完正的报道。

THE STUDY OF EFFERENT PROJECTIONS OF TORUS SEMICIRCULAR IN RING DOVE (STREPTOPELIA RISORIA)

The efferent projections of torus semicircularis in the midbrain of ring dove(Streptopelia risoria)were studied by using anterograde tracer ,PHA-L and Biocytin, delivered from iontophoretic application. Our results showed that the efferent projections from the medial margin of the inferior colliculus (ICM)were via two routes:The first group of labeled fibers left ICM and passed caudally into the region surrounding the dorsal nucleus of the lateral leminiscus, pars ventralis(LLDv).Another group of efferent projections from ICM passed rostrally into the thalamic auditory nucleus,the nucleus ovoidale shell(Ov shell).Injections of PHA-L in the nucleus intercollicularis(ICo)proper labeled a terminal field in the nucleus anterior medialis hypothalami(AM).These terminal fields surrounding classic auditory nuclei formed an accessory auditory pathway which coursed parallel to the classic auditory pathways.Here is the first delail report that a direct circle of vocal-auditory-endocrine axis presents in the brain of avian.