THE EFFECT OF ULTRAVIOLET LIGHT ON PROTEIN AND NUCLEIC ACID SYNTHESIS IN THE EPIDERMIS

[摘要] Following the irradiation of human and guinea pig skin with ultraviolet light there is an immediate decrease in the incorporation of amino acids and nucleic acid precursors into the epidermis. This is followed within 72 hours by a phase of increased incorporation. Repeated irradiation of the guinea pig with ultraviolet light results in thickening of the epidermis without a large increase in the capacity to incorporate amino acids into protein. This observation suggests that with chronic exposure there is a balancing of the inhibitory and stimulatory effects of ultraviolet light, resulting in a qualitative alteration of cellular metabolism. Evidence has been presented supporting the hypothesis that the erythema from ultraviolet light is caused by the diffusion of metabolites from the damaged epidermal cells into the dermis.