FIG. 6.

α-Cell ablation does not prevent streptozotocin (STZ)-induced diabetes. A: Experimental design. One high dose of STZ (200 μg/g of mouse weight) was administered to Glucagon-DTR mice to ablate β-cells 1 week after massive DT-mediated α-cell removal. Animals were killed 2 weeks after STZ. B–G: Confocal images of pancreatic sections show DT-mediated α-cell ablation and STZ-mediated β-cell removal. White arrowheads show remaining α-cells after DT. Scale bars = 20 μm. H: Follow up of glycemia. All STZ-treated mice become hyperglycemic irrespective of DT administration. By contrast, animals that did not receive STZ remain normoglycemic (red ♦: Glucagon-DTR mice treated with both DT and STZ, n = 6; black ▼: Glucagon-DTR mice treated only with STZ, n = 6; black ■: untreated Glucagon-DTR mice, n = 3; red ▲: Glucagon-DTR mice treated only with DT). I: Body weight 15 days after STZ. All mice treated with STZ lose weight and develop typical diabetes symptoms. (A high-quality digital representation of this figure is available in the online issue.)