Watson A H
Department of Zoology, University of Cambridge, U.K.
Neuroscience. 1988 Jul;26(1):33-44. doi: 10.1016/0306-4522(88)90125-x.
Antibodies raised against GABA and glutamate were used to stain sections through locust thoracic ganglia for light and electron microscopy. Using a peroxidase-antiperoxidase method for light microscopy, the GABA antibody was shown to label inhibitory motor neurons thought to use GABA as their neurotransmitter, and the glutamate antibody to label excitatory motor neurons thought to use glutamate. An immunogold method was used to reveal labelled neuropilar processes in the electron microscope. Each antibody specifically labels a particular population of processes. With the GABA antibody, labelling is equally clear whether the processes concerned contain synaptic vesicles or not and is strongly contrasted against very low background levels. With the glutamate antibody, most processes show some affinity for the antibody, probably reflecting the presence of metabolic glutamate, however one population can be clearly distinguished by the presence of a much greater density of gold particles over synaptic vesicles. In the locust it appears, therefore, that the antibody can distinguish clearly between the metabolic and neurotransmitter pools of glutamate. It has been proposed that synaptic vesicles in GABAergic neurons have a different shape to those in glutamatergic neurons. This was supported by the electron microscope immunocytochemistry. Those showing GABA-like immunoreactivity contain predominantly pleomorphic agranular vesicles approximately 21 x 30 nm in diameter. Those showing glutamate-like immunoreactivity contain round agranular vesicles of about 38 nm in diameter. The GABA antibody appears to label all processes containing pleomorphic agranular vesicles. By contrast, some processes containing round agranular vesicles are not labelled by the glutamate antibody, even though the vesicles they contain are statistically identical in size to those in labelled profiles. With neither antibody was the labelling of glial cells greater than the background level.
用针对γ-氨基丁酸（GABA）和谷氨酸的抗体对蝗虫胸神经节切片进行染色，用于光学显微镜和电子显微镜观察。利用过氧化物酶-抗过氧化物酶方法进行光学显微镜观察，结果显示GABA抗体标记了被认为以GABA作为神经递质的抑制性运动神经元，而谷氨酸抗体标记了被认为以谷氨酸作为神经递质的兴奋性运动神经元。采用免疫金法在电子显微镜下揭示标记的神经纤维突起。每种抗体都特异性地标记特定的突起群体。使用GABA抗体时，无论相关突起是否含有突触小泡，标记都同样清晰，并且与极低的背景水平形成强烈对比。使用谷氨酸抗体时，大多数突起对该抗体都有一定亲和力，这可能反映了代谢型谷氨酸的存在，然而，通过突触小泡上金颗粒密度高得多这一特征，可以清楚地区分出一个群体。因此，在蝗虫中，该抗体似乎能够清楚地区分谷氨酸的代谢池和神经递质池。有人提出，GABA能神经元中的突触小泡与谷氨酸能神经元中的突触小泡形状不同。这一点得到了电子显微镜免疫细胞化学的支持。显示GABA样免疫反应性的细胞主要含有直径约21×30nm的多形性无颗粒小泡。显示谷氨酸样免疫反应性的细胞含有直径约38nm的圆形无颗粒小泡。GABA抗体似乎标记了所有含有多形性无颗粒小泡的突起。相比之下，一些含有圆形无颗粒小泡的突起没有被谷氨酸抗体标记，尽管它们所含的小泡在统计学上与被标记的轮廓中的小泡大小相同。两种抗体对神经胶质细胞的标记都不高于背景水平。
