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bioRxiv · 10.1101/2023.09.28.559604

Brainstem astrocytes regulate breathing and may affect arousal state in rats

Bishop, M.·SheikhBahaei, S.
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Abstract

Variations in arousal levels can impact respiratory patterns. However, whether changes in breathing behaviors can influence arousal state is not fully understood. In this study, we investigated the role of astrocytes in the preBotzinger complex (preBotC) in modulating arousal states via breathing in adult conscious rats. Using viral vector tools, we selectively interfered with astrocytic signaling in the preBotC. Rats with inhibited astrocytic signaling exhibited slower breathing rates and behaviors indicative of a calmer state, whereas enhanced purinergic signaling in preBotC astrocytes led to faster breathing and heightened arousal. Our findings reveal a key role for astrocyte-mediated mechanism in the preBotC that influences both respiratory behaviors and higher-order brain functions like arousal, suggesting a bidirectional link between breathing behaviors and mental states. Highlights- In this study, we used molecular approaches to interfere with vesicular signaling in preBotC astrocytes. - We showed that inhibiting vesicular release mechanisms in preBotC astrocytes are associated with calm behaviors: lower breathing and sigh rates, and longer sniffing time. - We showed that enhancing vesicular release mechanisms in preBotC astrocytes are associated with more aroused behaviors: higher breathing and sigh rates as well as shorter sniffing time.

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Bishop, M., SheikhBahaei, S.. 2023-09-29. Brainstem astrocytes regulate breathing and may affect arousal state in rats. https://doi.org/10.1101/2023.09.28.559604

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