Abstract
Serum creatine kinase (CK, EC 2.7.3.2.) isoenzyme MM was separated by agarose gel electrophoresis into three sub-bands: CK-MM1, CK-MM2 and CK-MM3. In order to achieve clear separation, electrophoresis was carried out for a period of 120 min. CK-MM subbands were analyzed in 30 healthy individuals and little inter-individual difference was found. The healthy value of CK-MM sub-bands obtained was as follows: CK-MM1=56.3±5.2 %, CK-MM2=29.5±4.8 % and CK-MM3=14.1±2.6%. Serial change in CK-MM sub-bands was demonstrated in 20 patients suffering from acute myocardial infarction. CK-MM3was markedly increased at 4-12 hours after onset of symptoms and decreased at early phase of acute myocardial infarction and gradually increased. The CK-MM sub-band patterns returned to normal at 36.48 hours after onset of symptoms. The ratio of CK-MM3and CK-MM1 (CK-MM3/CK-MM1), with a healthy value of 0.25±0.02, was elevated above normal at early phase of acute myorardial infarction in all of the patients. Therefore, CK-MM3/CK-MM1might be an excellent indicator in diagnosis of early phase of acute myocardial infarction.
