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bioRxiv · 10.1101/753095

Transient astrocytic Gq signaling underlies remote memory enhancement

Iwai, Y.·Ozawa, K.·Yahagi, K.·Tanaka, M.·Itohara, S.·Hirase, H.
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Abstract

Astrocytes elicit transient Ca2+ elevations induced by G protein-coupled receptors (GPCRs), yet their role in vivo remains unknown. To address this, transgenic mice with astrocytic expression of the optogenetic Gq-type GPCR, Opto1AR, were established, in which transient Ca2+ elevations similar to those in wild type mice were induced by brief blue light illumination. Activation of cortical astrocytes resulted in an adenosine A1 receptor-dependent inhibition of neuronal activity. Moreover, sensory stimulation with astrocytic activation induced long-term depression of sensory evoked response. At the behavioral level, repeated astrocytic activation in the anterior cortex gradually affected novel open field exploratory behavior, and remote memory was enhanced in a novel object recognition task. These effects were blocked by A1 receptor antagonism. On the other hand, compelling evidence for astrocytic Ca2+-induced diameter changes of arteries was not observed. Together, we demonstrate that GPCR-triggered Ca2+ elevation in cortical astrocytes has causal impacts on neuronal activity and behavior.

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Iwai, Y., Ozawa, K., Yahagi, K., Tanaka, M., Itohara, S., Hirase, H.. 2019-09-02. Transient astrocytic Gq signaling underlies remote memory enhancement. https://doi.org/10.1101/753095

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