title: [Creatine kinase and its isozymes].
abstract: Creatine kinase (CK; EC 2.7.3.2) is found in a variety of striated and smooth muscles, and the brain, and is an important enzyme regulator of high-energy phosphate production and utilization within contractile tissues. Serum CK activity is measured routinely as a sensitive indicator of injuries to the skeletal muscle and myocardium. CK has three isozymes (CK-MM, CK-MB and CK-BB) in cytoplasm and two isozymes (non-sarcomeric and sarcomeric) in mitochondria. CK isozymes provide more specific information about injured tissue because of their tissue distribution. CK-MM is useful in skeletal muscle diseases, such as muscle dystrophy, CK-MB in acute myocardial infarction (AMI), and CK-BB in brain damage and malignant tumor of the gastro-intestinal tract. CK-MB is measured either by enzyme activity or mass concentration and is measured as a marker not only in the diagnosis of AMI but also in suspected AMI and unstable angina. Mitochondrial CK, a useful indicator for pinpointing the severeness of muscle injuries, and CK-linked immunoglobulin are recognized as macro-CK because of their large molecular size.
authors.affiliation: Showa University School of Medicine.
authors.forename: Y
authors.initials: Y
authors.lastname: Takagi
authors.forename: T
authors.initials: T
authors.lastname: Yasuhara
authors.forename: K
authors.initials: K
authors.lastname: Gomi
mesh_terms: D000789:Angina, Unstable / Q000175:diagnosis; D015415:Biomarkers / Q000097:blood; D001927:Brain Diseases / Q000175:diagnosis; D004796:Clinical Enzyme Tests; D003402:Creatine Kinase / Q000097:blood*; D052276:Creatine Kinase, BB Form; D052279:Creatine Kinase, MB Form; D052283:Creatine Kinase, MM Form; D052281:Creatine Kinase, Mitochondrial Form; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D009136:Muscular Dystrophies / Q000175:diagnosis; D009203:Myocardial Infarction / Q000175:diagnosis; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D003402:Creatine Kinase; D052276:Creatine Kinase, BB Form; D052279:Creatine Kinase, MB Form; D052283:Creatine Kinase, MM Form; D052281:Creatine Kinase, Mitochondrial Form