title: Xanthine oxidase and guanase activities in normal and psoriatic epidermis.
abstract: Xanthine oxidase and guanase activities in normal and psoriatic epidermis were demonstrated and accurately assayed by the new micro-assay methods which rely on the isolation of 14C-labelled end-products, xanthine and uric acid, from the substrates, hypoxanthine and guanine, by electrophoresis on cellulose acetate membrane using 0.1 M borate buffer, pH 9.0. The average specific activities of xanthine oxidase and guanase in normal epidermis were 10.2 and 55.0 pmol/min/mg protein, respectively, and in psoriatic epidermis, 52.1 and 980.6 pmol/min/mg protein, respectively. Increased activities of these enzymes in psoriatic epidermis suggested that urate formation might be enhanced in the psoriatic lesions resulting from an increased turn-over of nucleic acids.
mesh_terms: D000328:Adult; D000368:Aged; D000619:Aminohydrolases / Q000378:metabolism*; D005260:Female; D006148:Guanine Deaminase / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000201:enzymology*; D012867:Skin / Q000201:enzymology*; D014527:Uric Acid / Q000097:blood; D014969:Xanthine Oxidase / Q000378:metabolism*
chemical_list: D014527:Uric Acid; D014969:Xanthine Oxidase; D000619:Aminohydrolases; D006148:Guanine Deaminase