Using standardized freeze wounds in cat corneas, we tested the efficacy of human recombinant Epidermal Growth Factor (EGF) to promote endothelial healing when solubilized in either phosphate buffered saline (PBS), 1% methylcellulose (MC), or sodium hyaluronate (NaHA), in final intraocular doses ranging from 2μg to 100μg of EGF. After 6 or 7 days' healing, animals were humanely sacrificed and corneal tissues were fixed and stained for light microscopy and computation of remaining wound areas.EGF in NaHA in final intraocular doses of 2 and 10μg prompted significantly more complete healing of transcorneal freeze wounds to endothelium compared with endothelium of eyes treated with NaHA control solution alone. EGF in PBS or in MC in doses ranging from 2–100μg/eye did not promote more complete wound healing than that seen in eyes treated with their respective vehicle solutions alone. All vehicle solutions were associated with similar degrees of wound healing, implying that they have no intrinsic healing properties.