FIGURE 6.

hSptlc2 deficiency increased pGSK3β. Hearts extracts from floxed- and hSptlc2 KO mice at the age of 4- (A) or 7-months (B) were subjected to immunoblotting of pAKT, AKT, pGSK, GSK3β, pAMPKα, and AMPKα in the presence (A) or absence of insulin treatment (A and B). Basal glucose uptake in hearts was measured following intravenous administration of 3 μCi 2-deoxy-d-[¹⁴C]glucose. After 40 min, hearts were perfused with saline and excised, and radioactive counts were measured to determine glucose uptake (C). hSptlc2 KO hearts were isolated and stained with periodic acid-Schiff (PAS) staining to identify cardiac glycogen stores in midventricular cross sections (D). Magnification of all panels is at × 20. Values are mean ± S.E., n = 5–6. Scale bar, 100 μm.