Research Highlight: Vascular Compartmentalization of Functional Hyperemia from the Synapse to the Pia

ENP team leader Serge Charpak and coll. now make a significant contribution towards understanding where in the vasculature blood flow regulation in response to sensory stimulation is generated (Rungta et al., 2018, Neuron). This process, termed “functional hyperemia” is a fundamental brain process that is altered in many degenerative diseases.  Understanding the spatial dynamics of functional hyperemia is important for better interpreting human brain imaging techniques, which use blood flow changes a surrogate measure of neuronal activity. Using many demanding technical approaches, Rungta et al. simultaneously monitored neuronal activity and Ca2+ signaling dynamics in mural cells (pericytes and smooth muscle cells), and mathematically modeled the behaviour of hemodynamic parameters in various vascular compartments of the mouse olfactory bulb (using both anesthetized and awake animals). The authors describe in great detail the heterogeneity of local hemodynamics from the juxta-synaptic capillaries to the arterioles in the pia matter following odor stimulation. The authors also demonstrate that the capillary network is a major contributor to functional hyperemia.  See more