Sugar transport by renal plasma membrane vesicles. Characterization of the systems in the brush-border microvilli and basal-lateral plasma membranes.

Uptake studies of D-and L-glucose were performed on vesicles derived from brush-border and basal-lateral membranes. The uptake of the sugars into the vesicles was osmotically sensitive and independent of glucose metabolism. In brush-border vesicles D-glucose but not L-glucose transport was Na-+-dependent, wn the presence of an initial Na+gradient. Basal-lateral membranes take up D-glucose faster than L-glucose, but the D-glucose uptake is significantly less sensitive to sodium removal and only moderately inhibited by phlorzin as compared to the prush-border fraction.