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 (endoR_a; C) and disappearance (R_d; 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.