Figure 1.

ER stress activates intrinsic apoptosis in islet cells. (a–c) Islets from wild-type C57BL/6, Bim^−/− or Puma^−/− mice were cultured in a control medium or in a medium containing 5 μM thapsigargin for 5 days (a) or 4 days (b), or 10 μg/ml tunicamycin for 4 days (c). The frequency of cells undergoing DNA fragmentation was measured by flow cytometry. Results represent mean±s.e.m. of n=4 independent experiments. **P<0.01 when comparing wild-type to Bim^−/− or wild-type to Puma^−/− islets cultured with thapsigargin or tunicamycin (two-way ANOVA)