TRPV4 channels oppose AngII-induced artery constriction. (A) Internal diameter records WT (right) and TRPV4^−/− (left) arteries pressurized to 60 mmHg. Solid horizontal bars mark the time when arteries were exposed to U46619 (100 nM) and AngII (100 pM). The forward slashes (//) in the traces indicate a gap of 15 min. (B) Plot of the percentage of the maximum vasoconstriction (AngII-induced contraction/U46619-induced contraction × 100) induced by application of various AngII concentrations to WT (n = 4) and TRPV4^−/− (n = 3) arteries. Solid lines are fits to the data with a dose–response function Y = maximal response + (maximal response − minimal response)/(1 + 10^{LogEC50 − X}). Data are means ± SEM (error bars; *, P < 0.05; two-tailed Student’s t test).