Activation of locus coeruleus noradrenergic neuronsrapidly drives homeostatic sleep pressure

Silverman, D.; Chen, C.; Chang, S.; Bui, L.; Zhang, Y.; Raghavan, R.; Jiang, A.; Darmohray, D.; Sima, J.; Ding, X.; Li, B.; Ma, C.; Dan, Y.

doi:10.1101/2024.02.29.582852

bioRxiv · 10.1101/2024.02.29.582852

Activation of locus coeruleus noradrenergic neuronsrapidly drives homeostatic sleep pressure

Silverman, D.·Chen, C.·Chang, S.·Bui, L.·Zhang, Y.·Raghavan, R.·Jiang, A.·Darmohray, D.·Sima, J.·Ding, X.·Li, B.·Ma, C.·Dan, Y.

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Abstract

Homeostatic sleep regulation is essential for optimizing the amount and timing of sleep, but the underlying mechanism remains unclear. Optogenetic activation of locus coeruleus noradrenergic neurons immediately increased sleep propensity following transient wakefulness. Fiber photometry showed that repeated optogenetic or sensory stimulation caused rapid declines of locus coeruleus calcium activity and noradrenaline release. This suggests that functional fatigue of noradrenergic neurons, which reduces their wake-promoting capacity, contributes to sleep pressure.

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Silverman, D., Chen, C., Chang, S., Bui, L., Zhang, Y., Raghavan, R., Jiang, A., Darmohray, D., Sima, J., Ding, X., Li, B., Ma, C., Dan, Y.. 2024-03-04. Activation of locus coeruleus noradrenergic neuronsrapidly drives homeostatic sleep pressure. https://doi.org/10.1101/2024.02.29.582852

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