Myofibril swelling

Tomberg E., and Nerbrink, O. (1984). Swelling of whole meat and myofibrils, Proc. 30th European Meeting of Meat Research Workers, Bristol, 3 10, 112,... 

Ferrans et al. (1969) noted ultrastructural changes in myofibrils, including mitochondrial swelling and disorganization. Catecholamines also produce changes in the activity of oxidative enzymes. The decline in the activity progresses to the point where necrosis is evident. Ancillary effects include loss of myocardial potassium and an increase in interstitial fluid. Intracellular calcium overload also develops as noted by Fleckenstein et al. (1974). It has been hypothesized that necrosis due to catecholamine overload may be caused by a defect in energy supply needed for the maintenance of cellular processes. 

Qtycogen depletiori Sarcolemmal disruption mitochondrial mitochondrial swelling relaxation amorphous densities of myofibrils... 

Rats given an acute ip injection of KCN showed minimal ultrastructural changes if animals died within 5 min. If mortality was delayed (10-15 min) there was sarcomere elongation, myofibril dissociation at the I-band, swelling and destruction of mitochondria, enlargement of sarcoplasmic reticulum vesicles, and capillary endothelial swelling (Susuki, 1968). 

Offer, G. and J. Trinick. 1983. On the mechanism of water holding in meat The swelling and shrinking of myofibrils. Meat Science 8 245-281. 

The swelling of insoluble proteins corresponds to the hydration of soluble proteins in that insertion of water between the peptide chains results in an increase in volume and other changes in the physical properties of the protein. For example, the diameter of myofibrils (cf. 12.2.1) increases to 2.5 times the original value during rinsing with l.Omol/L NaCl, which corresponds to a six-fold volume increase (cf. 12.5). The amount of water taken up by swelling can amount to a multiple of the protein dry weight. For example, muscle tissue contains 3.5-3.6 g water per g protein dry matter. 

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