National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China.
National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China.
Gen Comp Endocrinol. 2021 May 15;306:113753. doi: 10.1016/j.ygcen.2021.113753. Epub 2021 Mar 10.
γ-Aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system. We investigated its potential role as a neurotransmitter in the neuroendocrine Dahlgren cell population of the caudal neurosecretory system (CNSS) of the flounder Paralichthys olivaceus. The application of GABA in vitro resulted in a decrease in electrical activity of Dahlgren cells, followed by an increase of the number of silent cells, together with a decreased firing frequency of all three activity patterns (tonic, phasic, bursting). GABA receptor agonist etomidate decreased Dahlgren cell firing activity, in a similar way to GABA. The response to GABA was blocked by the GABA receptor antagonist bicuculline. GABA receptor gamma2 subunit (Gabrg2) and chloride channel (Clcn2) mRNA expression were significantly upregulated in the CNSS after GABA superfusion. These data suggest that GABA may modulate CNSS activity in vivo mediated by GABA receptors.
γ-氨基丁酸（GABA）是中枢神经系统中的主要抑制性神经递质。我们研究了它作为比目鱼尾部神经分泌系统（CNSS）中Dahlgren 神经内分泌细胞群体的神经递质的潜在作用。GABA 的体外应用导致 Dahlgren 细胞电活动减少，随后沉默细胞数量增加，同时三种活动模式（紧张性、阶段性、爆发性）的放电频率降低。GABA 受体激动剂依托咪酯以类似于 GABA 的方式降低 Dahlgren 细胞的放电活动。GABA 受体拮抗剂印防己毒素阻断了 GABA 的反应。GABA 超射后 CNSS 中 GABA 受体 γ2 亚基（Gabrg2）和氯离子通道（Clcn2）mRNA 表达显著上调。这些数据表明，GABA 可能通过 GABA 受体调节体内 CNSS 活性。
