Ultrastructure of reperfused skeletal muscle: the effect of oxygen radical scavenger enzymes.
The aim of the present study was (1) to examine changes in ultrastructure and subcellular volume fractions in reperfused skeletal muscle and (2) to examine the effect of pre- plus postischaemic treatment with oxygen radical scavenger enzymes. Experiments were performed in 8 pentobarbital anesthetized dogs. The gracilis muscle was denervated and vascularly isolated on both lower limbs, except for the main artery and vein. A catheter was advanced through the distal end of the femoral artery for supply of superoxide dismutase (SOD) and catalase (each enzyme 12,000 U/10 min prior to ischaemia and 36,000 U/30 min at reperfusion) through the muscle artery to the muscle on one side. A catheter in the muscle vein secured the collection of venous blood to avoid a supply of SOD and catalase to the other muscle. Ischaemia was induced on both sides by clamping the branch of the femoral artery supplying the muscle for 4 h, and the muscle was thereafter reperfused for 1 h. Ultrastructural examination (morphometric by point counting and semiquantification) of the reperfused tissue revealed mitochondrial damage, margination of nuclear chromatin, lipid droplets, filamental disruption, as well as oedema in both endothelial and myofibrillar cells. In addition some influence of treatment with SOD and catalase could be seen, mainly in reduction of the number of micrographs with cellular oedema and especially oedema in endothelial cells.
Ytrehus
K
K
Institute of Medical Biology, University of Tromsø, Norway.
Reikerås
O
O
Huseby
N
N
Myklebust
R
R
D000818:Animals; D002374:Catalase / Q000627:therapeutic use*; D003402:Creatine Kinase / Q000097:blood; D004285:Dogs; D005260:Female; D016166:Free Radical Scavengers / Q000627:therapeutic use*; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply / Q000187:drug effects* / Q000648:ultrastructure; D010100:Oxygen; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D013482:Superoxide Dismutase / Q000627:therapeutic use*
D016166:Free Radical Scavengers; D002374:Catalase; D013482:Superoxide Dismutase; D003402:Creatine Kinase; D010100:Oxygen