Ultraviolet radiation induces changes in membrane metabolism of human keratinocytes in culture.

Human keratinocytes in culture were prelabeled with [3H]arachidonic acid (AA) and then exposed to ultraviolet B radiation. Irradiated cells released labeled AA metabolites into media in a dose-dependent manner when compared to sham-irradiated cells. The response began immediately and continued for 24 h. Extracts from media were examined by high-performance liquid chromatography for identification of specific AA metabolites. Irradiated cells were stimulated to produce prostaglandin-like material (PGE2 and PGF2 alpha). These findings support the concept that the cell membrane of keratinocytes participates directly or indirectly in initiating the sunburn response. It is also felt that the metabolites formed following injury to the membrane are an integral component in the mediation of that response.