Definition and difference of creatine kinase isoenzyme and creatine kinase

Creatine kinase (CK) exists widely in various tissues. CK consists of two subunits, M and B, which combine into three isoenzymes: CK-BB, CK-MM and CK-MB. There is another isoenzyme in the mitochondria of cells. CK-BB mainly exists in brain, prostate and other organs, CK-MM mainly exists in bones and myocardium, and CK-MB mainly exists in myocardium. The blood of most normal people is CK. Therefore, it can be found that CK and CK-MB increase when myocardial infarction occurs.