Figure 2.

Ouabain inhibits EGF-induced Erk1/2 and Akt signaling. DAOY cells were incubated for 15 min with EGF in the presence or absence of 50 μmol/L ouabain. (A) Activation of the MAPK signaling cascade was monitored by immunoblotting with phospho-specific anti-Erk1/2 and anti-Raf antibodies. Total Erk1/2 and actin levels confirm equal loading, respectively. (B) Activation of the Akt signaling cascade was determined with anti-phospho-Akt and anti-phospho-GSK antibodies that recognize only the activated forms of these proteins. Equal loading of cell lysate was confirmed with total Akt and actin immunoblots, respectively. EGF, epidermal growth factor.