Creatine kinase

Creatine Kinase (also known as CK) is an enzyme found in the heart, brain, skeletal muscle, and other tissues. Increased amounts of creatine kinase are released into the blood when there is muscle damage. This test measures the amount of creatine kinase in the blood.

Overview

Creatine kinase is a type of protein known as an enzyme. It speeds up certain biochemical reactions, specifically the conversion of creatine and uses adenosine triphosphate (ATP) to create phosphocreatine and adenosine diphosphate (ADP). This reaction is reversible, so CK also helps to regenerate ATP. ATP is a molecule that provides energy for muscle contractions and other processes in the body.

Types of Creatine Kinase

There are three different types of CK, each one present in different tissues:

• CK-MM: This type is primarily found in skeletal muscle and the heart.
• CK-MB: This type is primarily found in the heart and rises when heart muscle is damaged.
• CK-BB: This type is primarily found in the brain and smooth muscle (such as the intestines and uterus).

Creatine Kinase Test

A creatine kinase test may be used to detect inflammation of muscles (myositis) or serious muscle damage, or to diagnose rhabdomyolysis if a person has symptoms. It may be ordered along with or following an ALT test.

See Also

• Myocardial infarction
• Rhabdomyolysis
• Myositis

References

• Creatine Kinase Test
• Creatine Kinase MB
• Creatine Kinase BB

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  Structure of creatine kinase
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  Diagram of creatine kinase reaction
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  Blood values sorted by mass and molar concentration