Histology of the pancreas from T7K24R × Ctrb1-del mice at 3, 4, and 6 weeks of age. For comparison, pancreas section from a 6-week-old C57BL/6N mouse is shown. Representative hematoxylin-eosin stained pancreas sections are shown. The scale bars correspond to 50 μm. Note that the phenotype at 3 weeks of age was variable, see text for details. Although not shown, pancreas histology of 6-week-old T7K24R and Ctrb1-del mice was normal, indistinguishable from that of C57BL/6N controls.