Saint Marie R L, Benson C G, Ostapoff E M, Morest D K
Department of Anatomy, University of Connecticut Health Center, Farmington 06030.
Hear Res. 1991 Jan;51(1):11-28. doi: 10.1016/0378-5955(91)90003-r.
The aim of the present study was to investigate whether projections from the dorsal cochlear nucleus (DCN) to the anteroventral cochlear nucleus (AVCN) use either of two inhibitory transmitters, glycine or GABA. Retrograde HRP labeling of DCN-to-AVCN projection neurons was combined with postembedding immunocytochemistry in the DCN of guinea pigs. Following injections of HRP in the anterior or posterior divisions of AVCN, large numbers of neurons were labeled in the DCN. All of these were located in the deep layer, except for a few granule cells. Nearly all (96%) of the projection neurons were immunoreactive for glycine and most had dendritic and somatic morphologies corresponding to those of elongate neurons (so-called 'corn' cells); only a few resembled small stellate neurons. Few (3%) retrogradely labeled neurons were immunoreactive for GABA. The results suggest that projections from the deep DCN to the AVCN are formed primarily by glycinergic elongate neurons. These projections could have a substantial inhibitory influence on the output of neurons in the AVCN.
本研究的目的是探究从背侧耳蜗核（DCN）到前腹侧耳蜗核（AVCN）的投射是否使用两种抑制性递质之一，即甘氨酸或γ-氨基丁酸（GABA）。将DCN到AVCN投射神经元的逆行辣根过氧化物酶（HRP）标记与豚鼠DCN中的包埋后免疫细胞化学相结合。在AVCN的前部分或后部分注射HRP后，DCN中有大量神经元被标记。除了少数颗粒细胞外，所有这些神经元都位于深层。几乎所有（96%）的投射神经元对甘氨酸呈免疫反应，并且大多数具有与细长神经元（所谓的“玉米”细胞）相对应的树突和体细胞形态；只有少数类似于小星状神经元。很少（3%）逆行标记的神经元对GABA呈免疫反应。结果表明，从深层DCN到AVCN的投射主要由甘氨酸能细长神经元形成。这些投射可能对AVCN中神经元的输出产生实质性的抑制作用。
