FIG. 3.

Pancreatic β-cell hyperplasia and insulinoma in Men1^loxP/loxP/Rip-cre⁺ mice. (a to d) β-Cell hyperplasia in a 4-month-old Men1^loxP/loxP/Rip-cre⁺ mouse (a and c) compared to a Men1^loxP/loxP/Rip-cre⁻ littermate (b and d). Staining was done with hematoxylin and eosin (H&E) (a and b; magnification, ×20) and with a horseradish peroxidase-conjugated mouse anti-insulin antibody (c and d; magnification, ×20) (brown). (e to h) Pancreatic islet cell tumor and islet cell hyperplasia in a Men1^loxP/loxP/Rip-cre⁺ mouse. Staining was done with H&E (e and f; magnifications, ×20 and ×200, respectively). Immunoperoxidase staining (brown) of islet cell lesions was done with a mouse anti-insulin antibody (g and h; magnifications, ×20 and ×200, respectively).