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.