Purine phosphoribosyltransferase activities in guinea pig epidermis.
Purine phosphoribosyltransferase activities in normal and experimental hyperkeratotic epidermis of guinea pig skin were demonstrated quantitatively by a new microassay method. The ratio of HGPRTase with hypoxanthine as a substrate to APRTase activity in normal and hyperkeratotic epidermis was found to be 0.94 and 0.60, respectively. The HGPRTase and APRTase activities expressed as micromoles per gram wet weight per min. were increased in experimental hyperkeratotic epidermis and it is suggested that the salvage pathway for purine nucleotide biosynthesis is activated in experimental hyperkeratotic epidermis. The pH optimum of these enzymes and their stability in the frozen state were also demonstrated.
Department of Dermatology, Tokai University, School of Medicine, Isehara, 259-11, Japan.
I
I
Matsuo
M
M
Ohkido
H
H
Kizaki
T
T
Sakurada
D000818:Animals; D002846:Chromatography, Affinity; D004195:Disease Models, Animal; D004591:Electrophoresis, Polyacrylamide Gel; D004817:Epidermis / Q000201:enzymology / Q000378:metabolism; D006168:Guinea Pigs; D007564:Japan; D007642:Keratosis / Q000201:enzymology* / Q000473:pathology*; D008297:Male; D010430:Pentosyltransferases / Q000378:metabolism*; D012016:Reference Values; D012680:Sensitivity and Specificity
D010430:Pentosyltransferases; C022484:purine phosphoribosyltransferase