AKT inhibitor eliminates the phosphorylation of eNOS (Ser1177). MDBK cells with or without pre-treatment of AKT inhibitor for 30 min were challenged with GH at 200 ng/ml for 0. 15 and 30 min respectively. At the indicated time points, proteins were extracted from MDBK cells using the ProteoExtract® subcellular extraction kit (Calbiochem) and Western blot analyses were performed. Caveolin was used as a membrane protein marker. AKTi: AKT inhibitor. AKTi + GH: Cells pretreated with AKT inhibitor for 30 min before GH administration.