Figure 9.

Effects of H₂O₂ on glucose-induced insulin secretion and viability in INS-1 cells. INS-1 cells were incubated in the presence of glucose (8.3 mmol·L⁻¹) and in the absence or presence of increasing concentrations (10–1000 µmol·L⁻¹) of H₂O₂. Insulin secretion was quantified by the homogeneous time resolved fluorescence method. Viability was evaluated using the MTT assay. Data are expressed relative to the responses determined in the absence of H₂O₂, taken as 100%. Results are presented as mean ± SEM (n = 4–6 separate experiments). A multiple comparison analysis of data was performed for each type of experiment (insulin secretion or cell viability). Bars with the same letter do not differ significantly (P > 0.05).