Role of nitric oxide in ischemia-reperfusion injury and acute rejection in rat intestinal transplantation.
OBJECTIVE
This study was designed to evaluate the role of nitric oxide (NO) in ischemia-reperfusion injury (IRI) and acute rejection (AR) in rat intestinal transplantation, using administration of the NO inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME).


METHODS
Rats that underwent orthotopic allogeneic intestinal transplantation were assigned to 2 groups. In the normal allograft group (Wistar to Sprague-Dawley rats), L-NAME 0 mg/kg/d (group 1-1), 4 mg/kg/d (group 1-2), 8 mg/kg/d (group 1-3), or 12 mg/kg/d (group 1-4) was injected intraperitoneally. In the high responder allograft group (Dark Agouti to Lewis rats), L-NAME 0 mg/kg/d (group 2-1) or 8 mg/kg/d (group 2-2) was injected intraperitoneally. Survival times were observed and maltose absorption tests performed as well as light microscopic examination of the grafts.


RESULTS
The mean survival time of group 1-3 was significantly prolonged compared with group 1-1 (P < .01). In group 2, the survival time of group 2-2 was significantly prolonged compared with group 2-1 (P < .01). Histological changes showed IRI was attenuated in group 1-2 compared with group 1-1, whereas it was aggravated in groups 1-3 and 1-4. Treatment with L-NAME (8 mg/kg/d) attenuated the graft damage of AR in groups 1 and 2. Maltose absorption tests showed that inhibition of NO impaired maltose absorption.


CONCLUSIONS
This study suggested that NO plays a dual role as both a cytotoxic and a cytoprotective factor in IRI, and may serve as a kind of cytotoxic medium in AR in rat intestinal allotransplantation.
Li
X L
XL
Department of General Surgery, Second Affiliated Hospital of Harbin Medical University, Harbin, China.
Zou
X M
XM
Gao
P
P
Li
Y L
YL
Wang
H
H
Chen
X W
XW
D000818:Animals; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D006084:Graft Rejection / Q000503:physiopathology* / Q000517:prevention & control*; D006085:Graft Survival / Q000187:drug effects; D007408:Intestinal Absorption; D007422:Intestines / Q000098:blood supply / Q000473:pathology / Q000637:transplantation*; D008297:Male; D008320:Maltose / Q000378:metabolism; D019331:NG-Nitroarginine Methyl Ester / Q000627:therapeutic use*; D009569:Nitric Oxide / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000503:physiopathology* / Q000517:prevention & control*; D015996:Survival Rate; D014184:Transplantation, Homologous / Q000401:mortality / Q000502:physiology
D004791:Enzyme Inhibitors; D009569:Nitric Oxide; D008320:Maltose; D019331:NG-Nitroarginine Methyl Ester