During contraction of the muscle, ATP is constantly maintained due to
(A) Creatinine kinase # THE STRENGTH ENZYME SYSTEM: When muscle strength is required, ATP is created quickly form the following chemical reaction. The enzyme creatine kinase mediates ATP production from the high energy molecule creatine phosphate by an anaerobic reaction: CP + ADP > ATP + Creatine The CP (Creatine Phosphate) is depleted in just a few seconds. To continue producing high strength power, the speed enzyme system kicks in.> Creatine kinase (CK), also known as creatine phosphokinase (CPK) or phospho-creatine kinase (and sometimes incorrectly as creatinine kinase), is an enzyme expressed by various tissues and cell types.> CK catalyses the conversion of creatine and consumes adenosine triphosphate (ATP) to create phosphocreatine (PCr) and adenosine diphosphate (ADP).> This CK enzyme reaction is reversible, such that also ATP can be generated from PCr and ADP. 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.> Clinically, creatine kinase is assayed in blood tests as a marker of Myocardial infarction, Rhabdomyolysis, Muscular dystrophy, the Autoimmune Myositides and in Acute Renal Failure.
Creatinine kinase
Sodium potassium ATPase
Myosin kinase
Phosphokinase
Misc.