Figure 4. DP2 agonist-induced Ca²⁺ flux in human mast cells.

After measuring baseline fluorescence of Fluo-4 AM loaded MC (1.25×10⁵ cells in 50 µL/well), (A, C) DK-PGD₂ or (B, D) 15R-15-methyl PGD₂ was given to the MC and intracellular Ca²⁺ flux was assessed by measuring fluorescence change. (A, B) Cytosolic free Ca²⁺ changes induced by DP2 agonists are presented as ΔFluorescence ratio (fluorescence ratio of agonist treatment – fluorescence ratio of sham treatment), where fluorescence ratio is fluorescence unit at each time point/baseline fluorescence unit. Arrow indicates the time when agonist was given. (C, D) Cytosolic free Ca²⁺ changes induced by DP2 agonist treatment are presented as ΔIntegral for 3 min from ΔFluorescent ratio curves shown in A and B. Results are expressed as mean ± SEM for three separate experiments. *p<0.05, **p<0.01 compared with 100 nM agonist treatment by repeated measures ANOVA followed by the Bonferroni post-test.