Kim Yong-Jung, Nam Ryoung-Hee, Yoo Young Mi, Lee Chang-Joong
Department of Biological Sciences, College of Natural Sciences, Inha University, Incheon, South Korea.
Neurosci Lett. 2004 Jan 23;355(1-2):29-32. doi: 10.1016/j.neulet.2003.10.024.
The distribution of GABA-containing neurons was studied in the brain of the adult zebrafish by Nissl staining and immunohistochemistry. GABA immunoreactivity (GABA-IR) was demonstrated in parts of the brain such as olfactory bulb (OB), telencephalon, tectum stratum, and in the hypothalamus. GABA-IR appeared in the area where Nissl-stained cell bodies were abundant. The internal cellular layer of the OB was most densely stained by Nissl staining, and also showed a high level of GABA-IR. The telencephalon and the hypothalamus revealed a similar pattern to the OB in terms of Nissl staining and GABA-IR. However, the distribution and shape of stained cells of the tectum stratum were distinct from those in other regions: Nissl-stained neurons were ubiquitously present throughout all cellular layers including the stratum griseum centrale, the stratum album centrale (SAC), and the stratum periventriculare (SP). However, GABA-IR was weakly expressed in a limited number of neurons only in the SAC and SP. Whether GABA serves as an inhibitory neurotransmitter was also tested in the isolated telencephalon preparation by using extracellular field potential recordings. The synaptic activity recorded in the posterior dorsal telencephalon in response to the electrical stimulation of the anterior dorsal telencephalon was increased in the presence of the GABAA receptor antagonist, BMI, suggesting an inhibitory role for GABA-immunoreactive neurons in the adult brain of the zebrafish.
通过尼氏染色和免疫组织化学方法，研究了成年斑马鱼大脑中含γ-氨基丁酸（GABA）神经元的分布情况。在大脑的部分区域，如嗅球（OB）、端脑、视顶盖层和下丘脑，均检测到了GABA免疫反应性（GABA-IR）。GABA-IR出现在尼氏染色显示细胞体丰富的区域。嗅球的内细胞层尼氏染色最深，同时也显示出高水平的GABA-IR。端脑和下丘脑在尼氏染色和GABA-IR方面呈现出与嗅球相似的模式。然而，视顶盖层染色细胞的分布和形态与其他区域不同：尼氏染色的神经元普遍存在于所有细胞层，包括中央灰质层、中央白质层（SAC）和室周层（SP）。然而，GABA-IR仅在SAC和SP中有限数量的神经元中弱表达。还通过使用细胞外场电位记录，在分离的端脑标本中测试了GABA是否作为抑制性神经递质。在存在GABAA受体拮抗剂BMI的情况下，记录到的对前背侧端脑电刺激的后背侧端脑突触活动增加，这表明GABA免疫反应性神经元在成年斑马鱼大脑中具有抑制作用。
