page_title: Exertional rhabdomyolysis
section_title: Anatomy
hierarchical_section_title: Exertional rhabdomyolysis / Mechanism / Anatomy
caption_attribution_description: English: Motor end plate of a person with rhabdomyolsis. (Tidied-up version of original image).
context_page_description: Exertional rhabdomyolysis is the breakdown of muscle from extreme physical exertion. It is one of many types of rhabdomyolysis that can occur, and because of this the exact prevalence and incidence are unclear.
context_section_description: Exertional rhabdomyolysis results from damage to the intercellular proteins inside the sarcolemma. Myosin and actin break down in the sarcomeres when ATP is no longer available due to injury to the sarcoplasmic reticulum. Damage to the sarcolemma and sarcoplasmic reticulum from direct trauma or high force production causes a high influx of calcium into the muscle fibers increasing calcium permeability. Calcium ions build up in the mitochondria, impairing cellular respiration. The mitochondria are unable to produce enough ATP to power the cell properly. Reduction in ATP production impairs the cells ability to extract calcium from the muscle cell. 
   The ion imbalance causes calcium-dependent enzymes to activate which break down muscle proteins even further. A high concentration of calcium activates muscle cells, causing the muscle to contract while inhibiting its ability to relax. 
   The increase of sustained muscle contraction leads to oxygen and ATP depletion with prolonged exposure to calcium. The muscle cell membrane pump may become damaged allowing free form myoglobin to leak into the bloodstream.
caption: Motor end plate of a person with rhabdomyolysis
exif: {}