Fig. 1. Effect of acute administration of Pi on ³²P uptake into duodenal and jejunal BBMVs. Freshly prepared brush border membrane vesicles (BBMVs) from duodenal (A) and jejunal mucosa (B) of rats intragastrically gavaged with saline (NaCl-ig, n≥ 5) or with Pi (Pi-ig, n≥ 10) as well as of rats intravenously infused with saline (NaCl-iv, n≥ 7) or with Pi (Pi-iv, n≥ 5) were incubated with ³²P and ³H-glucose in the presence of cold substrate as described in Material and Methods. For each rat, the Na⁺-dependent incorporation of ³²P was normalized to the Na⁺-dependent incorporation of ³H-glucose. Columns represent mean ± the standard error of the mean (SEM). Statistical comparisons were performed using one-way ANOVA, followed by the Bonferroni post-test with a confidence interval of 95%.