Fig. 3

ATP-induced [Ca2 +]i oscillations in Sca-1 + cells. A, ATP-induced [Ca2 +]i oscillations in nominally 0 mM Ca2 + solution. B, Statistical histogram showing that ATP dose-dependently increases the peak [Ca2 +]i. C, ATP dose–response curve with Hill function showing an EC50 of 7.84 µM for ATP in nominally 0 mM Ca2 + solution. D-F, ATP-induced [Ca2 +]i elevations in 2.4 mM Ca2 + solution. G, Typical recordings showing that 30 µM ATP-induced robust [Ca2 +]i oscillations. H, Depletion of intracellular stores by 1 µM thapsigargin (TG) eliminates ATP-induced [Ca2 +]i oscillations. I, The non-specific P2Rs blocker suramin (100 µM) also inhibits ATP-induced [Ca2 +]i oscillations. J, Statistical histogram of suramin effects. Summary data were obtained from 3 to 7 independent experiments. The ‘n’ with number in the graph is the number of cells measured under each treatment condition. Data are expressed as mean ± standard deviation (SD). Data were first tested by Shapiro–Wilk test for normality and then paired t tests were performed for B and E, and Ordinary one-way ANOVA (Tukey’s multiple comparisons test) was performed for J. A P < 0.05 is considered a statistically significant test, and statistically significant P-values between the two groups are shown on the graph