IDENTIFICATION AND ACTIVITY OF CYTOSOL CREATINE-PHOSPHOKINASE ENZYMESIN NORMAL AND DISEASED SKIN

Phosphocreatine molecules (PCR) in skin regenerate adenosine triphosph ate and help cutaneous tissue survive ischemia associated with skin fl aps, grafts, and hair transplantation procedures. In addition, PCR con centration in psoriasis is elevated many times above normal, indicatin g either overproduction of PCR by mitochondrial creatine phosphokinase (CPK) enzymes or a defect in cytosol CPK enzymatic activity. Skin CPK isoenzymes, before this study, have not been identified. Herein, for the first time, cytosol CPK enzymatic activity was measured in normal and psoriatic, involved and uninvolved skin, skin tumors, and mouse sk in and keratinocyte cell cultures. Creatine phosphokinase MM is the ma jor isoenzyme in normal, uninvolved psoriatic and mouse skin. Total CP K enzymatic activity was increased in psoriasis and skin tumors. These data clearly indicate that increased PCR concentration in a psoriatic skin is not a result of decreased cytosol CPK enzymatic activity.