<Tr> <Th> PubMed </Th> <Td> articles </Td> </Tr> <Tr> <Th> NCBI </Th> <Td> proteins </Td> </Tr> <P> Creatine kinase (CK), also known as creatine phosphokinase (CPK) or phosphocreatine 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 CK enzyme reaction is reversible and thus ATP can be generated from PCr and ADP . </P> <P> In tissues and cells that consume ATP rapidly, especially skeletal muscle, but also brain, photoreceptor cells of the retina, hair cells of the inner ear, spermatozoa and smooth muscle, PCr serves as an energy reservoir for the rapid buffering and regeneration of ATP in situ, as well as for intracellular energy transport by the PCr shuttle or circuit . Thus creatine kinase is an important enzyme in such tissues . </P>

What is the difference between cpk and ck
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