中缝背核至内耳投射的神经生物学标记

A Study of a Projection From the Dorsal Raphe Nucleus to the Inner Ear by Antrograde Label Tracing Technique

目的我们的前期研究表明中缝背核(dorsal raphe nucleus,DRN)和内耳之间存在传出神经联系。本研究的目的是探讨DRN向耳蜗的投射方式。方法将示踪剂生物素化葡聚糖胺(Biotinylated Dextrain Amine,BDA)注入猫的DRN区,10天后处死动物,取出耳蜗,行BDA染色,内耳毛细胞铺片。结果 1.在第一、二排外毛细胞内可见散在的BDA阳性的呈棕褐色深染的毛细胞,分布不规则,未见显色的内毛细胞。2.可见来自蜗轴方向的纤维向外毛细胞底部投射。结论中缝背核与耳蜗外毛细胞之间可能存在一种纤维联系;这一联系主要存在于第一、二排外毛细胞。

Objective We have proved the efferent nerve connections between DRN and inner ear in early research. The aim of this study is to investigate the way of projection from the dorsal raphe nucleus（DRN） to the inner ear. Methods Highly sensitive Biotinylated Dextrain Amine（BDA） was injected into DRN of cat, and the cochlea was taken after survival period of 10 days. BDA positive was observed in the spread piece of the inner ear hair cells. Results 1. It was found that rare hair cells labeled with BDA which is dark brown after imnmnohistoehemieal staining. These BDA-positive cells irregular distributed mainly in the first row and second row of outer hair cells, and haven＇ t see the staining in the inner hair cells. 2. It was found that several fibers eompanied with BDA-positive cells from modiolus to the bottom of the outer hair cell. Conclusion The present results suggest that a fibers connection between DRN and inner ear hair ceils may exist. The link is mainly exists in the first row and second row of outer hair cells.