The amplitude of the signal mass of quantal TRPV4 sparklets is larger than that of Ca_V1.2 sparklets under physiological extracellular Ca²⁺ conditions. (A and B) All-points histograms generated from TRPV4 (A) and Ca_v1.2 (B) sparklet records from arterial myocytes. The solid black lines represent best fits to the data with a multi-Gaussian function for TRPV4 (q = 48 nM) and Ca_v1.2 (q = 18 nM) sparklets. The insets show representative TRPV4 and Ca_v1.2 sparklet records (membrane potential = −70 mV; external Ca²⁺ = 2 mM). The broken red lines in the insets mark the amplitude of quantal TRPV4 sparklets. The solid red lines highlight basal [Ca²⁺]_i. TRPV4 sparklets were recorded in the presence of 100 nM GSK. (C) Bar plot of the Ca²⁺ signal mass of Ca_v1.2 (92 events) and TRPV4 (15 events) sparklets in arterial myocytes. Data are means ± SEM (error bars; *, P < 0.05; two-tailed Student’s t test).