Measurement of Creatine Kinase and Creatine Kinase – Mb Isoenzyme in Myocardial Infarction Patients

Creatine Kinase is a bundant in most tissues. Activities as high as 12000 IU/g and as 225 JU/g have been reported in striated muscle. There are
approximately 1600 IU of CK activity pergram in myocardium 15% to 30% of which is CK-MB. Results with sensitive mass assays have shown that most
skeletal muscle contain small amount (1-3%) of CK-MB when skeletal is injured, it produces increased amount of B subunits, just as it does during fetal
development. Transient increase the percentage of CK-MB: in skeletal muscle and elevations in circulating levels occur after a cute muscle injury
(including extremely rigorous exercies). (1,8,9)