polyclonal anti-ERK1/2 antibody, the monoclonal anti-phospho-ERK1/2 antibody,
the monoclonal anti-c-Src antibody (B12), the monoclonal anti-insulin receptor
β subunit antibody, and the anti-rabbit- and the anti-mouse-conjugated
horseradish peroxidase second antibodies were obtained from Santa Cruz
Biotechnology (Santa Cruz, CA, USA); the polyclonal anti-phospho-Src pY418 and
the polyclonal anti-phospho-Src pY529 antibodies were obtained from Invitrogen
(Carlsbad, CA. USA); the monoclonal anti-α1 antibody α6 f was
obtained from the Developmental Studies Hybridoma Bank at the University of Iowa
and used for Western blot; the recombinant human Src was from Upstate (Lake
Placid, NY, USA). Chemiluminescence ECL kit was purchased from PerkinElmer
(Rockford, IL, USA). [3H]Ouabain was purchased from
DuPont NEN (Boston, MA, USA). Radioactive 86Rb+was from PerkinElmer Life Science Products (Boston, MA, USA). Other chemicals of
the highest purity were all obtained from Sigma–Aldrich (St. Louis, MO,
USA).