The cytosolic CK enzymes consist of two subunits, which can be either B (brain type) or M (muscle type). There are, therefore, three different isoenzymes: CK-MM, CK-BB and CK-MB.
The creatine kinase test measures the blood levels of certain muscle and brain enzyme proteins. Creatine kinase (CK or CPK) is an enzyme (a type of protein) found in muscle and brain. Normally, very little CK is found circulating in the blood. Elevated levels indicate damage to either muscle or brain; possibly from a myocardial infarction (heart attack), muscle disease, or stroke Creatine kinase (CK) — also known as creatine phosphokinase (CPK) or phospho-creatine kinase — is an enzyme (EC 2.7.3.2) expressed by various tissues and cell types. CK catalyses the conversion of creatine and utilizes adenosine triphosphate (ATP) to create phosphocreatine (PCr) and adenosine diphosphate (ADP). ) This test is not specific for the type of CK that is elevated. Creatine kinase in the blood may be high in health and disease. Exercise increases the outflow of creatine kinase to the blood stream for up to a week, and this is the most common cause of high CK in blood. Creatine kinase is an enzyme that is present in all the muscles of the body and is a catalyst in the energy conversion process. Creatine kinase used in the body are of two types-for the muscles and for the brain. Any testing to check their levels will therefore have to factor in this difference and most will have a CKM or CKB test. Elevated levels of the enzyme, or any levels of it, is usually the first test for cardiac problems. Creatine kinase, more commonly known as CK, is an enzyme that is present in all muscle tissue of the body including the heart and the brain. The normal creatine kinase levels in a man are between 38 and 174 units/L; while a woman's creatine kinase levels range from between 96 to 140 units/L. There are two main recognized types of creatine kinase, type B and type M. The B and M stand respectively for brain and muscle.. Three isoenzymes of creatine kinase are recognized, CK-MM, CK-BB and CK-MB; these are formed from the basic B and M type of creatine kinase. In addition, a third category, mitochondrial creatine kinase, has at least two subcategories. All of these types give slightly different information in diagnostic testing This test is used to find damage to muscles in your body, including your heart muscle. Creatine kinase (CK) is an enzyme found in your muscles. Enzymes are proteins that help your body's cells do their jobs. The level of the CK enzymes rises when you have damage to muscle cells in your body. The three types of CK are called isoenzymes.  The enzyme creatine kinase (CK) is found to predominantly exist as two subunits, namely, B-brain type and M-muscle type. This leads to the formation of three isoenzymes-CK-MM, CK-MB and CK-BB. Different chromosomes are found to hold the genes for these subunits; the M subunit on 19q13 while the B subunit is on 14q32. Creatine Kinase. Creatine kinase or phosphocreatine kinase, also called creatine phosphokinase-an enzyme that is present in various types of tissues in a human body. It is present predominantly in brain and muscle. In the cells, the cytosolic CK enzymes consist of two subunits, which can be either B (brain type) or M (muscle type). There are, therefore, three different isoenzymes: CK-MM, CK-BB and CK-MB. The genes for these subunits are located on different chromosomes: B on 14q32 and M on 19q13. ) This test is not specific for the type of CK that is elevated. Creatine kinase in the blood may be high in health and disease. Exercise increases the outflow of creatine kinase to the blood stream for up to a week, and this is the most common cause of high CK in blood. The Test. A creatine kinase (CK) test may be used to detect inflammation of muscles (myositis) or serious muscle damage and/or to diagnose rhabdomyolysis if a person has signs and symptoms, such as muscle weakness, muscle aches, and dark urine. 
http://medical-dictionary.thefreedictionary.com/Creatine+Kinase+Test https://en.wikipedia.org/wiki/Creatine_kinase http://www.medicalhealthtests.com/askquestion/29/what-is-the-significance-of-a-slightly-elevated-cr.html http://kidneypedia.net/creatine-kinase.html http://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=167&ContentID=creatine_kinase_isoenzyme_serum http://www.creatine-monohydrate.org/creatine-kinase.htm https://en.wikipedia.org/wiki/Creatine_kinase https://labtestsonline.org/understanding/analytes/ck/tab/test
what are the types of creatinine kinase