Fig. 5.

GH and IGF-I synergize in Akt activation. A, Serum-starved MIN6 cells were treated with vehicle (−), bGH (500 ng/ml), or IGF-I (20 ng/ml) or cotreated with bGH plus IGF-I (G/I) for 15 min. Cell extracts were analyzed by immunoblotting with anti-pAkt and anti-total Akt, respectively. WB, Western blot. B, Densitometric analysis of pooled data, as in A, from five independent experiments. Fold increase in Akt activation is shown for each condition with the basal (vehicle control) set as 1. Data are mean ± sem (n = 5). a, P < 0.01 (compared with control); b, P < 0.01 (compared with either GH or IGF). C, Reanalyzed results of pooled data of Akt activation. In this display, the sum of pAkt levels induced by bGH alone plus IGF-I alone (referred to as GH + IGF) is set as 100% and compared with the pAkt level induced by bGH and IGF-I cotreatment (referred to as G/I). Data are mean ± sem (n = 5). P < 0.05 (G/I vs. GH + IGF).