Figure 4.

Glucose homeostasis. Fasting blood glucose (A), fasting plasma insulin (B), and fasting plasma c-peptide (C) levels at 3, 9, and 11 months of age (n = 7–10). D, Intraperitoneal ITT was performed in 11-month-old nonfasted mice by injecting mice (n = 8–10) with 1U/kg body weight insulin and subsequent sampling of blood glucose. E, Intraperitoneal GTT was performed in 11-month-old mice (n = 8–10) following a 12-hour fast by injecting mice with a 10% glucose solution at 0.01 mL/g bodyweight and sampling glucose before injection at 15, 30, 45, 60, 90, 120, and 150 minutes after injection. F, Area under the curve (AUC) of the GTT was calculated for both groups of mice. *, Significant difference between genotype (P < .05); †, significant interaction between age and genotype (P < .05); ‡, significant difference with age (P < .05).