Intestinal glucose and amino acid transport is stimulated by the serum- and glucocorticoid-inducible kinase isoforms SGK1, SGK2 and SGK3 and protein kinase B, which are in turn stimulated following activation of the phosphoinositol-3 kinase (PI3-kinase). The present study has been performed to explore whether pharmacological inhibition of PI3-kinase affects electrogenic jejunal transport of glucose and amino acids. In Ussing chamber experiments glucose (20 mM), phenylalanine (20 mM), glutamine (20 mM), cysteine (20 mM) and proline (20 mM) generated lumen negative transepithelial potential differences and short circuit currents (Iglc , Iphe , Igln , Icys , Ipro ), respectively, which gradually declined following application of the PI3 kinase inhibitor Wortmannin (1mM). Within 40 min Wortmannin treatment significantly decreased Iglc by 38 ± 10% (n=5), Iphe by 70 ± 7% (n=4), Igln by 69 ± 8% (n=4), Icys by 67 ± 8% (n=7) and Iprol by 79 ± 12% (n=3). A similar decline of Iglc was observed following application of the PI3 kinase inhibitor LY294002 (50 mM). Exposure to the inhibitors did not significantly alter transepithelial potential difference and resistance in the absence of substrates for electrogenic transport. The observations suggest that the electrogenic transport of glucose and several amino acids requires the continued activity of PI-3 kinase.