FIG. 2.

Comparison of β₂AR^+/+ and β₂AR ^−/− pancreatic islets. Immunoistochemical analysis (A) of the islets was carried out on paraffin sections using insulin (left panel) or glucagon (right panel) antibodies. Microphotographs are representative of images obtained from pancreas sections of five 6-month-old β₂AR^+/+ (upper panel) or β₂AR ^−/− (lower panel) mice. Insulin (B) and glucagon (C) content in isolated islets from β₂AR^+/+ (n = 10) or β₂AR ^−/− (n = 13) mice. Insulin secretion in response to basal (2.8 mmol/L) or high (16.7 mmol/L) glucose concentration and to KCl (33 mmol/L) was measured in isolated islets from β₂AR^+/+ (□) and β₂AR^−/− (■) mice (D). Bars represent means ± SE of data from 10 mice per group. *P < 0.05 vs. β₂AR^+/+, Bonferroni post hoc test. (See also Supplementary Fig. 1.) (A high-quality digital representation of this figure is available in the online issue.)