Fig. 6. Activation by serum of Erk1/2 and Akt in E10, C10, and HPL1D cells. Proliferating (50%) and confluent (100%) cells were serum starved for 48 h (AC). Total and activated Erk1/2 in E10 (A), C10 (B), and HPL (C) cells. Total Erk1/2 did not change with serum stimulation, and Erk1/2 were rapidly activated to Erk1P/2P in both proliferating and confluent E10, C10, and HPL cells. D-F. Total and activated phosphorylated pAkt in E10 (D), C10 (E), and HPL (F) cells. Total Akt did not change with serum stimulation, and pAkt rapidly increased in both proliferating and confluent E10, C10, and HPL cells after serum stimulation.