Lysyl oxidase activity in human normal skins and postburn scars

Lysyl oxidase activity of human normal skins derived from the frontal thighs of 33 subjects showed large variations and the mean value was 11 455 +/- 7 172 (S.D.) cpm/g of wet weight tissue. The age of lesion affected the lysyl oxidase activity in postburn scars. Granulation tissues showed a fairly low activity; however, the activity increased sharply within 2--3 months, and reached a significantly higher value than that of normal skin. The high level of activity continued for up to 2--3 years, then gradually decreased to normal range after 5 years or so. Lysyl oxidase activity was detected only after 4 M urea treatment of tissues. Benzylamine oxidase activity also showed large variations in both normal skins and postburn scars, with mean values of: 0.128 +/- 0.077 (S.D.) and 0.145 +/- 0.090 (S.D.) mmol/g of wet weight/h, respectively. No correlation was observed between lysyl oxidase and benzylamine oxidase activities. The granulation tissues showed significantly high values of benzylamine oxidase activity in contrast to the low values of lysyl oxidase activity.