[Hydroxylation of skin collagen in relation to age: analyses of the human skin].

The results of human skin analysis are demonstrated. It has been pointed out, that the content of hydroxyproline and hydroxylysine, in addition to the usual variation as the other aminoacids varies extensively. The extent of hydroxylation was estimated from the relation of OH-aminoacids to (not hydroxylated) each other. The determined variation of the results is most probably due to a different collagen hydroxylation within the biological dispersion. An age-related degree of hydroxylation could not be detected.