Fex J, Altschuler R A, Kachar B, Wenthold R J, Zempel J M
Brain Res. 1986 Feb 26;366(1-2):106-17. doi: 10.1016/0006-8993(86)91285-0.
Antiserum raised against GABA coupled with glutaraldehyde to bovine serum albumin was applied to the guinea pig cochlea. Immunoreactivity was visualized as horseradish peroxidase reaction product in surface preparations of the organ of Corti using immunocytochemical techniques. Bright-field, differential interference contrast and video-enhanced contrast light microscopy were used. GABA-like immunoreactivity was found in axons and endings of efferent neurons in all turns of the cochlear spiral, but predominantly in the third turn and first half of the fourth turn. In these apical turns, immunoreactivity was seen in the efferent components: inner spiral bundle, tunnel spiral bundle, tunnel-crossing fibers, large nerve endings synapsing on outer hair cell bases, nerve endings high up on outer hair cells, nerve endings or varicosities close to outer hair cells, and outer spiral fibers. Some immunoreactive large nerve endings at outer hair cells were found in the apical half of the fourth turn. This study shows that axons and endings of efferent neurons in the organ of Corti of guinea pig contain GABA-like immunoreactivity with a distribution similar to that of GAD-like immunoreactivity as shown in a previous study. In both studies, many efferent nerve axons and endings were unstained, even in regions of maximal density of immunoreactivity in the apical turns. The evidence indicates that a subpopulation of efferent neurons projecting to the organ of Corti is GABAergic and very likely different from the lateral and the medial olivocochlear efferent systems.
将抗γ-氨基丁酸（GABA）与戊二醛偶联到牛血清白蛋白上制备的抗血清应用于豚鼠耳蜗。使用免疫细胞化学技术，在柯蒂氏器表面标本中，免疫反应性表现为辣根过氧化物酶反应产物。采用明场、微分干涉对比和视频增强对比光学显微镜进行观察。在耳蜗螺旋各圈的传出神经元轴突和终末中均发现了GABA样免疫反应性，但主要集中在第三圈和第四圈的前半部分。在这些顶端圈中，在传出成分中可见免疫反应性：内螺旋束、隧道螺旋束、隧道交叉纤维、在外毛细胞基部形成突触的大神经终末、外毛细胞上方高处的神经终末、靠近外毛细胞的神经终末或膨体以及外螺旋纤维。在第四圈的上半部分发现了一些在外毛细胞处有免疫反应性的大神经终末。本研究表明，豚鼠柯蒂氏器中传出神经元的轴突和终末含有GABA样免疫反应性，其分布与先前研究中所示的谷氨酸脱羧酶（GAD）样免疫反应性相似。在两项研究中，即使在顶端圈免疫反应性密度最大的区域，许多传出神经轴突和终末也未被染色。证据表明，投射到柯蒂氏器的传出神经元亚群是γ-氨基丁酸能的，并且很可能与外侧和内侧橄榄耳蜗传出系统不同。
