Calpain inhibitor, calpeptin, protects beta cells from hIAPP-induced death. INS 832/13 cells were transduced with rIAPP or hIAPP adenovirus at 400 m.o.i. for 72 h (A) and 48 h (B). AU, arbitrary unit. Calpeptin (1.25 μm) was added 6 h post-transduction. Cell viability was assessed by cleaved caspase-3 immunoblotting (A) and PI incorporation (B). Data are the mean ± S.E. from three independent experiments; *, p < 0.05, hIAPP + calpeptin compared with hIAPP only. Casp, caspase; Cl.Casp-3, cleaved caspase-3; CNTL, control.