FIGURE 4.

WAT insulin signaling in vivo. A–E, for insulin signaling in WAT in vivo, male mice at 10–12 weeks of age were fasted for 6 h, injected intraperitoneally with saline or insulin at 10 units/kg of body weight, and sacrificed 10 min thereafter. A and B, insulin-stimulated site-specific phosphorylation of IR, IRS1, and Akt as assessed by immunoblotting analysis (n = 3–5 per group). For quantification, phosphoproteins were normalized to the corresponding total proteins. GAPDH served as loading control. A and C, expression of total IR and IRS1 relative GAPDH control. D, IRS1-associated PI3K activity; and E, Akt activity (n = 3–7 per group). Data are expressed as mean ± S.E. *, p < 0.05 for effect of genotype as determined by unpaired two-tailed Student's t test (B and C) or one-way ANOVA (D and E).