Astroglial adrenoreceptors modulate synaptic transmission and contextual fear memory formation in dentate gyrus. (February 2021)

• Record Type: Journal Article
• Authors: Shen, Weida; Chen, Shishuo; Xiang, Yingchun; Yao, Zheyu; Chen, Zhitao; Wu, Xitian; Li, Ling; Zeng, Ling-Hui
• Is Part Of: Neurochemistry international. Volume 143(2021)
• Publication Date: 2021-02
• Subjects: Norepinephrine -- Astrocytic calcium signaling -- Pre-synaptic NMDA receptor -- Synaptic transmission -- Learning and memory; Neurochemistry -- Periodicals; Neurochemistry -- Periodicals; Neurochimie -- Périodiques; Neurochemistry; Periodicals; 612.804205
• DOI: 10.1016/j.neuint.2020.104942
• Languages: English
• ISSNs: 0197-0186

Abstract

Abstract: Astrocytes perform various supporting functions, including ion buffering, metabolic supplying and neurotransmitter clearance. They can also sense neuronal activity owing to the presence of specific receptors for neurotransmitters. In turn, astrocytes can regulate synaptic activity through the release of gliotransmitters. Evidence has shown that astrocytes are very sensitive to the locus coeruleus (LC) afferents. However, little is known about how LC neuromodulatory norepinephrine (NE) modulates synaptic transmission through astrocytic activity. In mouse dentate gyrus (DG), we demonstrated an increase in the frequency of miniature excitatory postsynaptic currents (mEPSC) in response to NE, which required the release of glutamate from astrocytes. The rise in glutamate release probability is likely due to the activation of presynaptic GluN2B-containing NMDA receptors. Moreover, we showed that the activation of NE signaling in DG is necessary for the formation of contextual learning memory. Thus, NE signaling activation during fear conditioning training contributed to enduring changes in the frequency of mEPSC in DG. Our results strongly support the physiological neuromodulatory role of NE signaling, which is derived from activation of astrocytes. Highlights: Norepinephrine (NE) boosts astrocytic Ca 2+ signaling via the activation of alpha1A-adrenoceptors in dentate gyrus. Astrocytic Ca 2+ signaling regulates NE-induced synaptic plasticity in granule cells. NE enhances the mEPSC in granule cells, which is mediated by the activation of presynaptic GluN2B-containing NMDARs.