Tissue plasminogen activator inhibitor in the epidermis

The presence of a tissue plasminogen activator inhibitor in the epidermis was investigated. A partially purified tissue plasminogen activator from a Bowes melanoma cell line medium was used as a tissue plasminogen activator. Extracts of epidermis dissolved in a 10 mM phosphate buffer, pH 7.0, were found to contain a tissue plasminogen activator inhibitor. The same extracts also contained a urokinase inhibitor. It is not clear whether these inhibitors are the same. This study is the first to show the existence of a tissue plasminogen activator inhibitor in the epidermis.