We report that continual chemical stimulation of TRPV4 channels [PCa/PNa = 10 (25)] induces [Ca2+]i fluctuations that require TRPM4, a Ca2+- activated monovalent cation channel [PCa/PNa = 0.12 (26)] that has been linked to hypertension and Ca2+ oscillations and Ca2+ release from intracellular compartments in lymphocytes and macrophages (27–30). The gene discussed is TRPV4; the disease is posterior cortical atrophy.