Influence of tissue XXXX and @entity855 levels on postischemic recovery in @entity95 skeletal muscle.

@entity1734 @entity63 @entity95 @entity880 @entity855
The effect of energy substrate depletion and of high @entity880 (LA) load on the development of irreversible cell injury was evaluated in the lateral gastrocnemius muscle of @entity95 subjected to 4 hr of tourniquet hindlimb @entity63 . Three groups of animals were studied. Group I, high @entity855 - @entity63 , these animals were subjected to 4 hr of @entity63 ; group II, low @entity855 --low LA @entity63 , in this group the gastrocnemius muscle was electrically stimulated for 5 min during @entity63 conditions to reduce the glycogen store, a short reperfusion period was allowed after the stimulation in order to wash out the built up LA, and the muscle was then subjected to 4 hr of @entity63 ; group III, low @entity855 --high LA @entity63 , in this group glycogen was depleted as in group II, but no reperfusion period was allowed before the 4 hr period of @entity63 . In group I, @entity855 levels were well preserved during the @entity63 period, whereas in the substrate-deprived groups (II and III) a rapid depletion of @entity855 and @entity1734 (CP) occurred. The LA was twice as high in the "high LA" group (III) as in the "low LA" group (II) during the @entity63 period. The extent of injury was evaluated after 24 hr of reperfusion by measuring @entity855 and CP content, and contractile force and by light microscopy. No or minor cell damage was found in group I. In group III--high LA--no recovery was obtained in any of the variables used for evaluation. In group II--Low LA--there was a certain recovery. @entity855 and CP increased to about 35% and contractile force to 25% of control. Morphologically about 20% of the muscle cells appeared to be unaffected by the @entity63 insult. It is concluded that reduction of the glycogen available for @entity855 resynthesis during the @entity63 period drastically reduces the ability of skeletal muscle to withstand prolonged @entity63 . A high LA load seems to amplify the deleterious effects of a low initial substrate level.
