Role of 5-hydroxytryptamine type 3 receptors in the regulation of anxiety reactions
- Author:
DU YINAN
1
;
LI ZHIWEI
;
ZHAO YUKUI
;
HAN JING
;
HU WEIPING
;
LIU ZHIQIANG
Author Information
- Keywords: 5-Hydroxytryptamine type 3 receptor(5-HT3R); Anxiety; Medial prefrontal cortex; Amygdala; Hippocampus; Periaqueductal gray
- From: Journal of Zhejiang University. Science. B 2024;25(1):23-37
- CountryChina
- Language:Chinese
- Abstract: 5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT3R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+ and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT3R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT3Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety reactions.They have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT3Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and the γ-aminobutyric acid(GABA)"disinhibition"mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT3R-induced GABA"disinhibition"mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT2R-mediated regulation of anxiety reactions are also activated by 5-HT3R-activated 5-HT release in the HIP and PAG.This provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT3Rs.However,given the circuit specific modulation of 5-HT3Rs on emotion,systemic use of 5-HT3R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT3R drugs.Therefore,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.
