TY - JOUR TI - PIP2 depletion promotes TRPV4 channel activity in mouse brain capillary endothelial cells AU - Harraz, Osama F AU - Longden, Thomas A AU - Hill-Eubanks, David AU - Nelson, Mark T A2 - Csanády, László A2 - Aldrich, Richard VL - 7 PY - 2018 DA - 2018/08/07 SP - e38689 C1 - eLife 2018;7:e38689 DO - 10.7554/eLife.38689 UR - https://doi.org/10.7554/eLife.38689 AB - We recently reported that the inward-rectifier Kir2.1 channel in brain capillary endothelial cells (cECs) plays a major role in neurovascular coupling (NVC) by mediating a neuronal activity-dependent, propagating vasodilatory (hyperpolarizing) signal. We further demonstrated that Kir2.1 activity is suppressed by depletion of plasma membrane phosphatidylinositol 4,5-bisphosphate (PIP2). Whether cECs express depolarizing channels that intersect with Kir2.1-mediated signaling remains unknown. Here, we report that Ca2+/Na+-permeable TRPV4 (transient receptor potential vanilloid 4) channels are expressed in cECs and are tonically inhibited by PIP2. We further demonstrate that depletion of PIP2 by agonists, including putative NVC mediators, that promote PIP2 hydrolysis by signaling through Gq-protein-coupled receptors (GqPCRs) caused simultaneous disinhibition of TRPV4 channels and suppression of Kir2.1 channels. These findings collectively support the concept that GqPCR activation functions as a molecular switch to favor capillary TRPV4 activity over Kir2.1 signaling, an observation with potentially profound significance for the control of cerebral blood flow. KW - TRPV4 KW - neurovascular coupling KW - PIP2 KW - Kir2.1 KW - GPCR KW - brain capillaries KW - phosphoinositides KW - GqPCR JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -