Figure 4.

Effect of intravenous and intragastric administration of Pi on Pi and glucose transport activities in renal BBMVs from intact rats. Rats were loaded with 500 μmol Pi or saline intravenously or orally. Kidneys were extracted 40 minutes or 4 hours after infusion or gavage, and Na⁺–dependent and –independent Pi and glucose transport activities were measured. Pi transport was assayed in the presence or absence of the SLC34 transport inhibitor phosphonoformic acid. (A) ³²P uptakes 40 minutes after intravenous infusion of saline (gray bars) and Pi (black bars). (B) ³²P uptakes 40 minutes after intragastric administration of saline (gray bars) and Pi (black bars). (C) ³²P uptakes 4 hours after intravenous infusion of saline (gray bars) and Pi (black bars). (D) ³²P uptakes 4 hours after intragastric administration of saline (gray bars) and Pi (black bars). (E) ³H-d-glucose uptakes 40 minutes after intravenous and intragastric administration of saline (gray bars) and Pi (black bars). (F) ³H-d-glucose uptakes 4 hours after intravenous and intragastric administration of saline (gray bars) and Pi (black bars). Data are presented as the means±SEM. Unpaired t test; n=5–9 per group and time point. *P<0.05 versus saline group.