Figure 1.

SGLT1 expression in proximal small intestine of wild-type and Glp2r^−/− mice in response to consumption of varied levels of dietary carbohydrate. Wild-type (WT) and Glp2 receptor knockout (Glp2r^−/−) mice were fed low (L, □) or high (H, ■) carbohydrate diets as described in methods. (A) Steady state levels of SGLT1 mRNA abundance as determined by qPCR. (B left) SGLT1 protein abundance in brush-border membrane vesicles (BBMV) isolated from proximal small intestine measured by western blot analysis. (B right) densitometric analysis of western blots of SGLT1 protein abundance normalized to that of β-actin. (C) SGLT1-mediated glucose uptake determined by Na⁺-dependent D-[U¹⁴C] glucose uptake into same population of BBMV used in B, measured as pmol s⁻¹ (mg protein)⁻¹. All values are expressed relative to SGLT1 expression in the proximal small intestine of wild-type mice on low-carbohydrate diets for 5 d, as means ± SEM. Data were generated in triplicate, with n = 6–8 animals in each group. Statistically significance determined by Student's unpaired two-tailed t-test are indicated by *P < 0.05; ***P < 0.001.