Antonio Paoli, Pasqualina Cancellara, Pierluigi Pompei and Tatiana Moro
+ -dependent cysteine proteases. This process requires specific levels of Ca 2+ to activate the enzyme that leads to proteolysis ( Dargelos et al., 2008 ). Therefore, it seems that the calpain system is activated during muscle injuries, when cytosolic Ca 2+ levels rises ( Goll et al., 1992 ).
Methods for assessing muscle protein metabolism
Dynamic assessment of MPS and MPB can be determined using stable isotope methodologies ( Wolfe and Chinkes, 2005 ). Stable isotopes are non-radioactive molecules, naturally enriched with heavier atoms, which results in a different