FIGURE 8.

GIP stimulates Akt signaling in STS-treated INS-1 cells. A, INS-1 cells were treated with STS without or with GIP for 4 h without or with Akt inhibitor, 500 nm Akt IV, or PI3K signaling inhibitors (15 μm LY294002 or 5 μm Akt VIII), and Western analysis was performed on cell lysates and Akt KA assays with indicated antibodies. IP, immunoprecipitate. B, shown is the mean change ± S.E. in Akt activity (P-GST-GSK3/Akt) relative to control (n = 4). #, p < 0.05 versus control; $, p < 0.05 versus GIP without inhibitor. Anti-β-actin and anti-GST (GST-GSK3) blots were internal controls.