INDEX skeletal muscles, enzymes

Creatine kinase, creatine kinase myocardial band Creatine kinase (CK) enzymes are found in many isoforms, with varying concentrations depending on the type of tissue. Creatine kinase is a general term used to describe the nonspecific total release of all types of CK, including that found in skeletal muscle (MM), brain (BB) and heart (MB). CK MB is released into the blood from necrotic myocytes in response to infarction and is a useful laboratory test for diagnosing myocardial infarction. If the total CK is elevated, then the relative index (RI), or fraction of the total that is composed of CK MB, is calculated as follows RI = (CK MB/CK total) x 100. An RI greater than 2 is typically diagnostic of infarction. 

Muscle cells which arc damaged will leak creatine kina.se into the plasma. This enzyme exists in different isoforms. CK-MM or total CK is used as an index of skeletal mu.scle damage. Very high serum levels may be expected in patients who have been convulsing or have muscular damage due to electrical shock or crush injury. Creatine kinase concentrations may also be high in acute spells in muscular dystrophy. For these rea.sons, when CK is used as an indicator of myocardial infarction. it is better to measure the MB... 

---