Agonist dose-dependent Ca2+mobilization. (A) The changes in [Ca2+]i induced by various concentrations of OXT were measured in HEK-293 cells expressing hOXTR-376R-EGFP, hOXTR-376G-EGFP, or hOXTR-376C-EGFP. (B) Relationship between OXT concentrations and [Ca2+]i at the initial peak. Cells were infused with the indicated concentration of OXT. Each plot shows a percentage of [Ca2+]i at the initial peak after treatment with OXT. Data are mean ± standard error of the mean (n = 8 to 30 cells from three or four independent cultures; two to eight cells were analyzed in each culture). Statistical significance was evaluated by the Student’s t test (* P <0.05, **P <0.01; compared with hOXTR-376R-EGFP).