Serum and Glucocorticoid Regulated Kinase 1 (SGK1) is thought to mediate the hormonal regulation of epithelial Na+ absorption, however the involvement of this kinase is difficult to assess due to a lack of SGK1 inhibitors. In this study we evaluate a novel assay of SGK1 activity which may help clarify the role of SGK1. Dexamethasone (Dex) has been previously shown to stimulate both Na+ transport and sgk1 expression in the H441 Human Bronchiolar Epithelial cell line. Insulin also stimulates Na+ transport in these cells (20nM insulin increased apical Na+ conductance from 51.1 ± 10.6 to 74.9 ± 14.9mScm -2 n = 5 p < 0.05) and as SGK1 is activated downstream of PI-3-Kinase both Dex and insulin were expected to increase SGK1 activity. To investigate this we measured the abundance of the phosphorylated form of N-myc Downstream Regulated Gene 1 (NDRG1), a specific substrate of SGK1. Acute stimulation of H441 cells with Dex (200nM) lead to increased abundance of the phosphorylated protein, normalized to the total abundance of NDRG1 (n = 7 p < 0.05). Acute stimulation with insulin (20nM) also increased abundance of phosphorylated NDRG1 (n = 5 p < 0.001) while PI-3-Kinase inhibitor LY-294002 (50?M) decreased its abundance (n = 5 p < 0.01). These data suggest that the relative abundance of phosphorylated NDRG1 can be used effectively as an indicator of changes in SGK1 activity.