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bioRxiv · 10.1101/2022.07.14.500017

Sleep cycle-dependent vascular dynamics enhance perivascular cerebrospinal fluid flow and solute transport

Bojarskaite, L.·Bjornstad, D. M.·Vallet, A.·Binder, K. M. G.·Cunen, C.·Heuser, K.·Kuchta, M.·Mardal, K.-A.·Enger, R.
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Abstract

Perivascular spaces (PVS) are important highways for fluid and solute transport in the brain enabling efficient waste clearance during sleep. Using two-photon imaging of naturally sleeping mice we demonstrate sleep cycle-dependent PVS dynamics - slow, large-amplitude oscillations in NREM, a reduction in REM and an enlargement upon awakening at the end of a sleep cycle. By biomechanical modeling we demonstrate that these sleep cycle-dependent PVS dynamics drive fluid flow and solute transport.

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Bojarskaite, L., Bjornstad, D. M., Vallet, A., Binder, K. M. G., Cunen, C., Heuser, K., Kuchta, M., Mardal, K.-A., Enger, R.. 2022-07-16. Sleep cycle-dependent vascular dynamics enhance perivascular cerebrospinal fluid flow and solute transport. https://doi.org/10.1101/2022.07.14.500017

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