Epidermal growth factor (EGF) receptor was detected in the human Chang liver and human hepatoma HepG2 cells. Both cell lines were found to be able to bind EGF. The expression of EGF receptor in Chang liver and HepG2 cells was 1.3 x 10(5) EGF receptors/cell and 1.8 x 10(5) EGF receptors/cell, respectively. In both cells, this receptor was identified by ECL Western blotting using monoclonal anti-EGF receptor antibody and by immunohistochemical assay using polyclonal anti-EGF receptor antibody. Some of internalized EGF was recycled in Chang liver cells, but not in HepG2 cells.