Perivascular fibroblasts locally regulate the vasomotor dynamics of pial arterioles

Karas, S.; Harmon, E.; Bonnar, O.; Pawlikowski, B.; Jeffrey, D. A.; Munoz, L. M.; Lake, F.; Sosa Ibarra, M. J.; Nielson, C. D.; Dabertrand, F.; Siegenthaler, J. A.; Shih, A. Y.; Bonney, S. K.

doi:10.64898/2026.09.11.751046

bioRxiv · 10.64898/2026.09.11.751046

Perivascular fibroblasts locally regulate the vasomotor dynamics of pial arterioles

Karas, S.·Harmon, E.·Bonnar, O.·Pawlikowski, B.·Jeffrey, D. A.·Munoz, L. M.·Lake, F.·Sosa Ibarra, M. J.·Nielson, C. D.·Dabertrand, F.·Siegenthaler, J. A.·Shih, A. Y.·Bonney, S. K.

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Abstract

Perivascular fibroblasts (PVFs) ensheath pial arterioles on the brain surface, yet their physiological role on the healthy cerebrovasculature remains unknown. Here, we show that PVFs display calcium dynamics that are temporally aligned with arteriolar vasomotion. Depletion of fibroblasts disrupted vasomotion whereas enhancement of PVF-Gq signaling increased vasomotor activity and accelerated fluid influx into the peri-arteriolar space. These findings identify PVFs as unrecognized regulators of cerebral vasodynamics and cerebrospinal fluid movement.

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Karas, S., Harmon, E., Bonnar, O., Pawlikowski, B., Jeffrey, D. A., Munoz, L. M., Lake, F., Sosa Ibarra, M. J., Nielson, C. D., Dabertrand, F., Siegenthaler, J. A., Shih, A. Y., Bonney, S. K.. 2026-09-18. Perivascular fibroblasts locally regulate the vasomotor dynamics of pial arterioles. https://doi.org/10.64898/2026.09.11.751046

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