Diversity of neurovascular coupling dynamics along vascular arbors in layer II/III somatosensory cortex

• Published in: Communications biology 2021-07, Vol.4 (1), p.855-11, Article 855
• Main Authors: Rungta, Ravi L., Zuend, Marc, Aydin, Ali-Kemal, Martineau, Éric, Boido, Davide, Weber, Bruno, Charpak, Serge
• Format: Article
• Language: English
• Subjects: 14; 14/69; 631/378/2607; 631/378/3917; Anesthesia; Animals; Arterioles; Biology; Biomedical and Life Sciences; Blood; Blood flow; Brain; Brain - blood supply; Brain - physiology; Brain mapping; Brain Mapping - methods; Calcium signalling; Capillaries; Capillaries - physiology; Cerebral blood flow; Cerebral cortex; Cerebral Cortex - blood supply; Cerebral Cortex - physiology; Cerebrovascular Circulation - physiology; Female; Humans; Hyperemia; Life Sciences; Male; Mice; Mice, Inbred C57BL; Neuroimaging; Neuroimaging - methods; Neurons - physiology; Neurovascular Coupling - physiology; Olfaction; Olfactory bulb; Olfactory Bulb - blood supply; Olfactory Bulb - physiology; Somatosensory cortex; Somatosensory Cortex - blood supply; Somatosensory Cortex - physiology; Temporal cortex; Velocity; Vibrissae - physiology; Wakefulness - physiology
• ISSN: 2399-3642; 2399-3642
• DOI: 10.1038/s42003-021-02382-w

The spatial-temporal sequence of cerebral blood flow (CBF), cerebral blood volume (CBV) and blood velocity changes triggered by neuronal activation is critical for understanding functional brain imaging. This sequence follows a stereotypic pattern of changes across different zones of the vasculature in the olfactory bulb, the first relay of olfaction. However, in the cerebral cortex, where most human brain mapping studies are performed, the timing of activity evoked vascular events remains controversial. Here we utilized a single whisker stimulation model to map out functional hyperemia along vascular arbours from layer II/III to the surface of primary somatosensory cortex, in anesthetized and awake Thy1-GCaMP6 mice. We demonstrate that sensory stimulation triggers an increase in blood velocity within the mid-capillary bed and a dilation of upstream large capillaries, and the penetrating and pial arterioles. We report that under physiological stimulation, response onset times are highly variable across compartments of different vascular arbours. Furthermore, generating transfer functions (TFs) between neuronal Ca 2+ and vascular dynamics across different brain states demonstrates that anesthesia decelerates neurovascular coupling (NVC). This spatial-temporal pattern of vascular events demonstrates functional diversity not only between different brain regions but also at the level of different vascular arbours within supragranular layers of the cerebral cortex. Rungta et al. utilized single whisker stimulation to map out functional hyperemia along vascular arbours from layer II/III to the surface of primary somatosensory cortex, in anesthetized and awake Thy1-GCaMP6 mice. They demonstrated the presence of a functional diversity not only between different brain regions but also at the level of different vascular arbours within supragranular layers of the cerebral cortex.