@entity460 regulation and XXXX .

@entity2383 @entity2003 @entity3055 @entity8452 @entity425 @entity3999 @entity590 @entity11104 @entity74 @entity460 @entity141 @entity12740 @entity121 @entity855 @entity2472
Changes in intracellular @entity141 -concentration play an important role in the excitation-contraction-relaxation cycle of skeletal muscle. In this review we describe various inheritable @entity121 to highlight the role of @entity141 -regulatory mechanisms. Upon excitation the @entity8452 receptor releases @entity141 in the cytosol. During and after contraction the sarcoplasmic reticulum (SR) @entity141 ATPase (SERCA) pumps @entity141 back in the SR resulting in relaxation. An abnormal change in the intracellular @entity141 -concentration results in @entity121 and/or relaxation, which is the cause of various @entity121 . @entity590 ( @entity590 ) and @entity12740 ( @entity12740 ) are both caused by mutations in the @entity8452 receptor but show different clinical phenotypes. In @entity590 an acute increase of @entity141 results in excessive @entity2472 causing @entity2003 , while in @entity12740 a chronic rise of cytosolic @entity141 is seen, leading to @entity2383 , disorganization of myofibrils and @entity425 . In @entity11104 and also in @entity3055 , SERCA functions sub optimal causing a prolonged physiological @entity141 -elevation leading to slowing of relaxation. Defective actin- @entity3999 interactions, as in nemaline @entity121 and also in @entity3055 due to @entity855 -shortage, cause @entity141 -hyposensitivity and slowness of contraction. Information of @entity141 -kinetics in these @entity74 improves our understanding of the role of @entity460 in the physiology and pathophysiology of the skeletal muscle cell.
