The effect of a nitroxide antioxidant on ischemia-reperfusion injury in the rat in vivo hind limb model.
Microsurgical procedures such as free tissue transfer or replantations of amputated digits involve an obligatory ischemic period leading to regional tissue oedema, rhabdomyolysis, systemic acidosis, hypercalcemia and multiple organ dysfunction syndrome reflecting ischemia-reperfusion (I/R) injury. Since nitroxide stable radicals act as antioxidants their potential protective effects were tested. Anaesthetized Sabra rats were subjected to regional ischemia of the hind limb for 2 h using a tourniquet. Upon reperfusion rats were injected with 4-OH-2,2,6,6-tetramethylpiperidine-1-oxyl (TPL). Systemic I/R-induced damage was assessed by sampling blood for differential count, lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) serum levels. Regional injury was evaluated by analysing excised muscle samples for oedema (tissue water content) and inflammatory infiltrate (number of cell nuclei in histomorphometric analysis). I/R-induced changes of biomarkers reflecting systemic damage peaked about 8 h following the start of reperfusion and fully disappeared as the biomarkers relaxed to their pre-ischemic values after 24 h. TPL facilitated the recovery of some of these parameters and partially affected release of cellular CPK and LDH. The parameters of I/R-induced regional tissue injury did not demonstrate any recovery and were not inhibited by TPL.
Arieli
David
D
Department of Plastic Surgery, Hebrew University-Hadasah Medical School, Jerusalem, Israel.
Nahmany
Guy
G
Casap
Nardi
N
Ad-El
Dean
D
Samuni
Yuval
Y
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001772:Blood Cell Count; D003402:Creatine Kinase / Q000097:blood; D004195:Disease Models, Animal; D004576:Electromyography; D006614:Hindlimb / Q000098:blood supply; D007511:Ischemia / Q000188:drug therapy*; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology; D009589:Nitrogen Oxides / Q000494:pharmacology*; D010880:Piperidines / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000503:physiopathology
C110289:4-hydroxy-2,2,6,6--tetramethylpiperidine-1-N-hydroxyl; D000975:Antioxidants; D009589:Nitrogen Oxides; D010880:Piperidines; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase; C039900:nitroxyl