text: Chronic insulin (24 h) activates NHE3 through the classic << phosphatidylinositol 3-kinase >>-serum- and glucocorticoid-dependent kinase 1 (PI3K-SGK1) pathway as insulin stimulates SGK1 phosphorylation and the insulin effect can be blocked by the PI3K inhibitor [[ wortmannin ]] or a dominant-negative SGK1.