Figure 3.

Arsenic does not inhibit A23187 Ca2+ ionophore-stimulated degranulation in RBL-2H3 cells. RBL-2H3 cells were harvested and plated as described in the “Methods” section. Cells were stimulated to degranulate for 1 h with either (A) 1.5 × 10-7 M (which caused an average absolute degranulation response of 11.5% ± 2.8% [SEM]) or (B) 2.0 × 10-7 M (which caused an average absolute degranulation response of 18.1% ± 3.2% [SEM]) A23187 Ca2+ ionophore. Resultant β-hexosaminidase was measured as described in “Methods.” Values are means ± SEM from seven independent experiments per A23187 dose, each with three replicates per experiment. No statistical significance was determined by one-way ANOVA followed by Tukey's post- test, where multiple comparisons were made to the 100 ppb sample.