GABAA receptor-mediated inhibition of Dahlgren cells electrical activity in the olive flounder, Paralichthys olivaceus

Zhaohui Lan; Wei Zhang; Jinling Xu; Weiqun Lu

doi:10.1016/j.ygcen.2021.113753

GABA_A receptor-mediated inhibition of Dahlgren cells electrical activity in the olive flounder, Paralichthys olivaceus

Gen Comp Endocrinol. 2021 May 15:306:113753. doi: 10.1016/j.ygcen.2021.113753. Epub 2021 Mar 10.

Authors

Zhaohui Lan¹, Wei Zhang¹, Jinling Xu², Weiqun Lu³

Affiliations

¹ 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.
² 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.
³ 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. Electronic address: wqlv@shou.edu.cn.

PMID: 33711316
DOI: 10.1016/j.ygcen.2021.113753

Abstract

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_A receptor agonist etomidate decreased Dahlgren cell firing activity, in a similar way to GABA. The response to GABA was blocked by the GABA_A receptor antagonist bicuculline. GABA_A 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_A receptors.

Keywords: Caudal neurosecretory system; Electrophysiology; GABA; GABA(A) receptor; Teleost fish.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Flounder* / genetics
Neurosecretory Systems
Neurotransmitter Agents
Receptors, GABA-A / genetics
gamma-Aminobutyric Acid

Substances

Neurotransmitter Agents
Receptors, GABA-A
gamma-Aminobutyric Acid