Creatine Phosphokinase


Creatine Phosphokinase, Creatine Kinase, Creatine Phosphotransferase, CPK, CK-MB, CK-MM ( C0010291), CK-BB

  • Physiology
  1. Transferase class enzyme activated by Magnesium
  2. Catalyzes ATP energy storage as Phosphocreatine
  3. Phosphocreatine stored in Muscle and brain
  4. Phosphocreatine keeps ATP constant at Exercise start
  • Isoenzymes
  1. MB: Heart
  2. MM: Skeletal Muscle
  3. BB:
    1. Brain
    2. Bowel infarction
    3. Neoplasm (Prostate, GI, Breast, Ovary, Lung, Brain)
  1. Older protocol - replaced in United States with Troponin
  2. Obtain Serial CPK every 6 hours for total of 3 values
  3. Fractionate to CK-MB only if CPK increased
  4. CK-MB >5% of total CPK suggests Myocardial Infarction