Kong W J, Hussl B, Thumfart W F, Schrott-Fischer A
Department of Otolaryngology, University of Innsbruck, Austria.
Acta Otolaryngol. 1998 Jan;118(1):90-5. doi: 10.1080/00016489850155198.
Gamma-aminobutyric acid (GABA) is presumed to be a neurotransmitter candidate in the vestibular periphery of mammals. However, experimental reports about the localization of GABA in afferents or efferents of the vestibular systems are contradictory. It is an open question whether there are species differences in the amammalian vestibular system. The present study was designed to investigate the ultrastructural localization of GABA-like immunoreactivity in the vestibular periphery of the rat. A modified preembedding immunoelectron microscopy technique was applied using a polyclonal antibody to GABA as a marker. GABA-like immunoreactivity was revealed in the vestibular periphery of the rat, confined to the vesiculated nerve fibers and terminals of the rat vestibular neurosensory epithelia. Type I hair cells and type II hair cells as well as efferent chalices are devoid of GABA-like immunoreactive staining. These findings indicate that GABA is a neurotransmitter candidate of the efferent vestibular system of the rat.
γ-氨基丁酸（GABA）被认为是哺乳动物前庭外周的一种神经递质候选物。然而，关于GABA在前庭系统传入或传出纤维中定位的实验报告相互矛盾。哺乳动物前庭系统是否存在物种差异仍是一个悬而未决的问题。本研究旨在探讨大鼠前庭外周GABA样免疫反应性的超微结构定位。采用改良的包埋前免疫电子显微镜技术，以抗GABA多克隆抗体作为标记物。在大鼠前庭外周发现了GABA样免疫反应性，局限于大鼠前庭神经感觉上皮的囊泡状神经纤维和终末。I型毛细胞、II型毛细胞以及传出杯状细胞均无GABA样免疫反应性染色。这些发现表明，GABA是大鼠前庭传出系统的一种神经递质候选物。
