FIGURE 4.

Telmisartan enhances [Ca²⁺]_i levels through extracellular Ca²⁺ influx, rather than intracellular Ca²⁺ stores release. (A) The trace shows the changes of [Ca²⁺]_i concentration in β-cells treated with telmisartan (Tel, 10 μM) under 16.7 mM glucose conditions in Ca²⁺-free KRBH medium. (B) The average value of F340/F380 during each test in response to telmisartan (Tel, 10 μM) in Ca²⁺-free KRB medium (n = 23 cells). (C) The trace shows the changes of [Ca²⁺]_i concentration in β-cells treated with telmisartan (Tel 10 μM) under 16.7 mM glucose conditions with addition of the L-type VGCC blocker azelnidipine (Az, 0.1 μM). (D) The mean value of F340/F380 during each test in response to telmisartan (10 μM) with added azelnidipine (0.1 μM). Thapsigargin (Thap, 0.1 μM) was used as a positive control (n = 12 cells). The cells compared between the groups in each graph are isolated from the same animal. All results are reported as the means ± SEM. Statistical differences among three or more groups were determined by one-way ANOVA, followed by Tukey Test post hoc analysis. *p < 0.05.