Fig. 6.
Inhibition of signaling pathway regulated by CaSR of [Ca2+]e- or [Sr2+]e-mediated calcitonin secretion in 6-23 cells. The inhibition of Gi/o protein signaling pathway was achieved by 24-h preincubation of the Gi/o protein inhibitor pertussis toxin. The inhibition of the PI3-K signaling pathway was achieved by 10-min preincubation of the PI3-K inhibitors wortmannin and LY294002. The inhibition of ERK1/2 phosphorylation was achieved by 10-min preincubation of the MEK1 inhibitor PD98059. Responses were normalized to the calcitonin secretory response at 10 mM cation. Statistical comparisons of the values were performed by using a one-way ANOVA of each condition, and Dunnett's post-tests were used to compare DMSO control response for each cation to the inhibitors responses for each cation (n = 6).