Guastella J, Johnson C D, Stretton A O
Neuroscience Training Program, University of Wisconsin, Madison 53706.
J Comp Neurol. 1991 May 22;307(4):584-97. doi: 10.1002/cne.903070406.
gamma-Aminobutyric acid (GABA) immunoreactive neurons in the cephalic, somatic, and caudal regions of the Ascaris nervous system were visualized with serial section and whole-mount GABA immunocytochemistry. In the ventral and dorsal nerve cords, GABA-like immunoreactivity (GLIR) is localized to the neurites and cell bodies of identified inhibitory motor neurons and to two fibers, one in each cord, that arise from neurons in the nerve ring. GLIR is absent from identified excitatory motor neurons and from ventral cord interneurons. In neurons containing GLIR, immunoreactivity was present throughout the cell, which argues against an exclusive localization of GABA at conventional synapses. In whole mounts, ten GABA-immunoreactive neurons were present in the cephalic region. These include four nerve ring-associated cells (the RME-like cells), two bilaterally symmetrical pairs of lateral ganglia neurons (the amphid-GABA and deirid-GABA cells) and one bilaterally symmetrical pair of ventral ganglion cells (the VG-GABA cells). In sections, the RME-like cells and the VG-GABA cells were consistently stained through the cephalic region. However, anti-GABA staining of the lateral ganglia cells in sections was light, thus suggesting that they contain less GLIR than the other more intensely stained GABA-immunoreactive neurons. In the caudal region, a single GABA-immunoreactive neuron was present in the dorsal rectal ganglion. Our data suggest that these ten cephalic neurons, and a single dorsal rectal ganglion neuron, use GABA as a neurotransmitter.
利用连续切片和整装 GABA 免疫细胞化学技术，观察了蛔虫神经系统头端、体部和尾端区域中 γ-氨基丁酸（GABA）免疫反应性神经元。在腹侧和背侧神经索中，GABA 样免疫反应性（GLIR）定位于已确定的抑制性运动神经元的神经突和细胞体，以及神经环中神经元发出的两条纤维，每条神经索各有一条。已确定的兴奋性运动神经元和腹侧神经索中间神经元中不存在 GLIR。在含有 GLIR 的神经元中，整个细胞都有免疫反应性，这表明 GABA 并非仅定位于传统突触。在整装标本中，头端区域有 10 个 GABA 免疫反应性神经元。其中包括 4 个与神经环相关的细胞（类 RME 细胞）、两对双侧对称的侧神经节神经元（ amphid-GABA 细胞和 deirid-GABA 细胞）以及一对双侧对称的腹侧神经节细胞（VG-GABA 细胞）。在切片中，类 RME 细胞和 VG-GABA 细胞在整个头端区域均持续染色。然而，切片中侧神经节细胞的抗 GABA 染色较浅，这表明它们所含的 GLIR 比其他染色更强烈的 GABA 免疫反应性神经元少。在尾端区域，背侧直肠神经节中有一个单一 GABA 免疫反应性神经元。我们的数据表明，这 10 个头端神经元和一个背侧直肠神经节神经元将 GABA 用作神经递质。
