Effect of nitric oxide on the contractile function of rat reperfused skeletal muscle.
BACKGROUND
The involvement of nitric oxide (NO) in ischemia-reperfusion injury remains controversial and has been reported to be both beneficial and deleterious. The purpose of this study was to examine the contribution of NO and superoxide to skeletal muscle function using an ischemic revascularized hind limb model in rats.


METHODS
Warm ischemia produced by vascular pedicle clamping was sustained for 3 h. The animals were divided into four groups according to the solution administrated: (1) saline, (2) N-methyl-L-arginine acetate (L-NMMA), (3) L-NMMA + N-(N-L-g-glutamyl-S-nitroso-l-cysteinyl)glycine (S-nitrosoglutathione), or (4) superoxide dismutase (SOD). Saline, L-NMMA, or L-NMMA + S-nitrosoglutathione was infused for the first 2 h of reperfusion. The SOD was administered as an intravenous bolus 5 min before the onset of reperfusion. Postischemic blood flow was measured by a Doppler flow meter. Muscle contractile function was determined after 24 h of reperfusion.


RESULTS
Postischemic blood flow was significantly decreased by the L-NMMA infusion compared with that in the saline-treated group. No significant difference in postischemic blood flow was noted in the saline-, L-NMMA + S-nitrosoglutathione-, and SOD-treated groups. Contractile function of the gastrocnemius muscle in the L-NMMA-and SOD-treated groups, but not in the L-NMMA + S-nitrosoglutathione group, was significantly better than that in the saline-treated group.


CONCLUSIONS
Limiting postischemic blood flow and SOD infusion are both beneficial in decreasing the ischemia-reperfusion injury of skeletal muscle. S-Nitrosoglutathione infusion following suppression of endogenous NO production does not reduce ischemia-reperfusion injury.
Department of Orthopedic Surgery, Kumamoto University School of Medicine, Kumamoto, Japan.
Kenshiro
K
Ikebe
Teiji
T
Kato
Makio
M
Yamaga
Toru
T
Tsuchida
Hiroki
H
Irie
Yasunari
Y
Oniki
Katsumasa
K
Takagi
D000818:Animals; D004195:Disease Models, Animal; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology*; D018482:Muscle, Skeletal / Q000098:blood supply / Q000502:physiology*; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D051381:Rats; D011917:Rats, Inbred Lew; D015427:Reperfusion Injury / Q000503:physiopathology*; D026422:S-Nitrosoglutathione / Q000494:pharmacology; D019323:omega-N-Methylarginine / Q000494:pharmacology
D004791:Enzyme Inhibitors; D020030:Nitric Oxide Donors; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione