[Modification of relative amount of free amino acids in the stratum corneum of human epidermis by special factors of the environment. I. The influence of UV-irradiation (author's transl)].

By repeated uv-irradiation the quantity of all free amino acids (per surface unit) in human horny layer increase considerably. 4 different groups of substances are found by taking the relative values in mole per cent. 1. No difference for urea, threonine, serine, glutamine, tyrosine and ammonia. 2. Decrease of about 20 p.c. for glutaminic acid, citrulline, arginine, histidine. 3. Increase of about 20 p.c. for urocanic acid, aspartic acid, proline, glycine, valine, isoleucine. 4. The rest of amino acids increase about 30--50 p.c.