Tissue Fibrinolytic Activity in Sunburn Erythema and Psoralen-UVA-Induced Erythema

Abstract

This experiment was carried out in order to investigate in sequence with time the tissue fibrinolytic activity in sunburn erythemas and psoralen-UVA-induced erythemas. Tissue fibrinolytic activity increased in the upper dermis in PUVA erythemas and the lower dermis in sunburn erythemas one to 6 hours after irradiation. When increased, sun-burn erythemas began, and reached their maximum at 6 to 12 hours, and declined gradually with decreasing of its activity at over 12 hours. PUVA erythemas did not appear yet at this time and began approximately 18 hours after the beginning of exposure, when its activity decreased in the upper dermis. After 96 hours when PUVA erythemas reached a peak intensity, its activity disappeared in the upper dermis, but was found in the lower dermis.