Fig. 7.
Eact causes minor increases in intracellular calcium concentrations ([Ca2+]i) with 0 external calcium and does not increase inositol trisphosphate (IP3) synthesis. A: representative tracings of fura 2 calcium fluorescence in human primary airway smooth muscle (ASM) cells in 0 external Ca2+. B: bradykinin (Brady) caused a significant increase in [Ca2+]i (0.32 ± 0.01, n = 18, P < 0.001), whereas Eact caused a significant but small increase in [Ca2+]i (0.05 ± 0.01, n = 18, *P < 0.05 and ***P < 0.001). C: Eact did not cause an increase in IP3 synthesis, whereas bradykinin increased IP3 synthesis (positive control, n = 4, *P < 0.05). All treatments were done in 3–4 different primary ASM cell lines. One-way ANOVA with post hoc Bonferroni’s test.