Regulation of Endogenous Glucose Production in Glucose Transporter 4 Over-Expressing Mice
Figure 1
Hormonal and glucose flux responses to acutely normalizing blood glucose in glucose transporter 4 over-expressing mice (G4Tg) and wild-type (WT) littermates.
A 90 min phloridzin (80 μg·kg−1·min−1)-glucose (115 mg·dL−1) clamp was performed in conscious, chronically-catheterized, 5 h-fasted mice that over-express glucose transporter 4 (Glut4) in skeletal muscle, heart, and adipose tissue and wild-type (WT) littermates to normalize basal differences in arterial blood glucose (A) using an exogenous glucose infusion rate (B). Basal and clamp endogenous appearance (endoRa; C) and disappearance (Rd; D) of glucose were measured using a primed, constant infusion of [3-3H] glucose (50 μCi bolus +0.05 μCi·min−1). Basal and clamp arterial insulin, non-esterified fatty acids (NEFA), and glucagon are shown in panels E-G, respectively. Data are presented as means ± SEM and * and ϕ indicate p<0.05 compared to WT littermates or to basal values within a genotype, respectively. n = 7–8 mice in each group.