Metallothionein prevention of diabetes-induced superoxide generation in the heart. A: Superoxide generation was probed by immunofluorescent staining using dihydroethidine, which specifically reacts with superoxide,
in the heart of wild-type control, diabetic, and insulin-treated diabetic mice. B: In addition, the whole heart was also collected from the mice 2 weeks after STZ treatment and freshly processed for measuring
NADPH-dependent superoxide generation using a cytochrome c reduction method, as described in the research design and methods. Treatment groups that do not share the same letter were significantly different (P < 0.05).