Fex J, Altschuler R A
Hear Res. 1986;22:249-63. doi: 10.1016/0378-5955(86)90102-4.
The principles of immunocytochemistry were outlined in 1942 by Coons et al. and in the 1970's immunocytochemistry emerged as a powerful method for identifying structures and tracing pathways in the nervous system. It now plays a fundamental role in the neuroanatomical and histochemical analysis of the central nervous system. The first immunocytochemical studies of the mammalian cochlea were reported in 1980, from three different laboratories. Since then many studies on cochlear immunocytochemistry have been carried out, concerned with questions about neurotransmitter candidates or about structural proteins. This review describes immunoreactivity of enkephalin, choline acetyltransferase (ChAT), glutamate decarboxylase (GAD), gamma-aminobutyric acid (GABA), aspartate aminotransferase (AATase) and glutaminase (GLNase) in the organ of Corti. ChAT is the enzyme that catalyzes the synthesis of acetylcholine (ACh). GAD is the terminal enzyme in the biosynthesis of the inhibitory neurotransmitter GABA. AATase and GLNase are two enzymes involved in the metabolism of the excitatory neurotransmitter candidates aspartate and glutamate. We have much relied on surface preparations of the organ of Corti. We have also used cryostat sectioning of the cochlea, particularly when there was a need to apply a number of different antisera to comparable preparations from one and the same cochlea. We have used immunofluorescence and immunoperoxidase procedures. Immunoperoxidase procedures have given us better signal noise ratio for specific immunoreactivity (in surface preparations) than has immunofluorescence. Occasionally, to achieve maximal resolution of surface preparations in light microscopy studies, we have used enhanced contrast video display. We have found immunoreactivity in efferent fibers in the organ of Corti following the application of antisera to enkephalin, ChAT, GAD, GABA, AATase and GLNase. Most of these different antisera give different distributions of immunoreactivity and other antisera have evoked no immunoreactivity in the organ of Corti. To the best of our knowledge, the cells of origin of efferent axons and terminals in the organ of Corti are located in the brainstem. Originally described as crossed and uncrossed olivocochlear neurons, these efferents have recently been classified into a medial and a lateral system predominantly innervating, respectively, the outer hair cell region and the inner hair cell region. However, our findings on the distribution of GAD- and GABA-like immunoreactivity indicate that there may be more than two different systems of efferents in the organ of Corti, as previously suggested by Schwartz and Ryan (1983).
1942年，孔斯等人概述了免疫细胞化学的原理。到了20世纪70年代，免疫细胞化学成为一种用于识别神经系统结构和追踪神经通路的强大方法。如今，它在中枢神经系统的神经解剖学和组织化学分析中发挥着重要作用。1980年，来自三个不同实验室的研究报告了对哺乳动物耳蜗的首次免疫细胞化学研究。从那时起，人们对耳蜗免疫细胞化学进行了许多研究，涉及神经递质候选物或结构蛋白相关的问题。本综述描述了在柯蒂氏器中脑啡肽、胆碱乙酰转移酶（ChAT）、谷氨酸脱羧酶（GAD）、γ-氨基丁酸（GABA）、天冬氨酸转氨酶（AATase）和谷氨酰胺酶（GLNase）的免疫反应性。ChAT是催化乙酰胆碱（ACh）合成的酶。GAD是抑制性神经递质GABA生物合成中的末端酶。AATase和GLNase是参与兴奋性神经递质候选物天冬氨酸和谷氨酸代谢的两种酶。我们在很大程度上依赖于柯蒂氏器的表面标本。我们也使用了耳蜗的低温切片技术，特别是当需要对来自同一个耳蜗的可比标本应用多种不同抗血清时。我们使用了免疫荧光和免疫过氧化物酶方法。与免疫荧光相比，免疫过氧化物酶方法在表面标本中为特异性免疫反应性提供了更好的信噪比。偶尔，为了在光学显微镜研究中实现表面标本的最大分辨率，我们使用了增强对比度的视频显示。在对脑啡肽、ChAT、GAD、GABA、AATase和GLNase应用抗血清后，我们在柯蒂氏器的传出纤维中发现了免疫反应性。这些不同的抗血清大多给出了不同的免疫反应性分布，而其他抗血清在柯蒂氏器中未引发免疫反应性。据我们所知，柯蒂氏器中传出轴突和终末的起源细胞位于脑干。这些传出神经最初被描述为交叉和不交叉的橄榄耳蜗神经元，最近被分为内侧和外侧系统，分别主要支配外毛细胞区域和内毛细胞区域。然而，我们关于GAD和GABA样免疫反应性分布的发现表明，柯蒂氏器中可能存在不止两种不同的传出神经系，正如施瓦茨和瑞安（1983年）之前所建议的那样。
