Effect of ornithine on the ileal histology, nitric oxide production and lipid peroxidation in LPS-induced endotoxemia.
Effect of ornithine which is known to inhibit L-arginine uptake via cationic amino acid transport system has been tested, and compared to aminoguanidine, an iNOS inhibitor in lypopolysaccharide (LPS)-induced endotoxemia in rats. Serum nitrite/nitrate and malondialdehyde (MDA) level have been measured, and ileal histology has also been examined. Endotoxin increased serum nitrite/nitrate and MDA levels from 15.7+/- 2.4 micromol/ml and 2.1 +/-0.2 nmol/ml to 23.1 +/- 1.0 micromol/ml and 5.2+/- 0.3 nmol/ml (both P<0.05), respectively. In addition, LPS caused ileal degeneration. L-ornithine (500 mg/kg) did not improve septic manifestations, i.e., serum nitrite/nitrate and MDA levels did not differ from those in endotoxemia. Neither does it have an improving action on ileal histology. However, higher dose of L-ornithine (2,500 mg/kg) lowered the increased level of nitrite/nitrate and MDA by LPS. Moreover, it restored ileal histology from grade 3 (median) to 0 (median) (P<0.05). On the other hand, aminoguanidine (100 mg/kg) normalized serum nitrite/nitrate and MDA levels but not ileal histology in endotoxemic rats. In conclusion, high dose of L-ornithine could improve endotoxemic parameters in LPS-treated rats.
Dirlik
Musa
M
Department of Surgery, Mersin University, Mersin, Turkey. musa_dirlik@yahoo.com
Büyükafşar
Kansu
K
Cinel
Ismail
I
Cinel
Leyla
L
Caglikülekçi
Mehmet
M
Tamer
Lülüfer
L
Aydin
Süha
S
Oral
Ugur
U
D000818:Animals; D004305:Dose-Response Relationship, Drug; D019446:Endotoxemia / Q000097:blood / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006146:Guanidines / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*; D015227:Lipid Peroxidation / Q000187:drug effects*; D008070:Lipopolysaccharides; D008315:Malondialdehyde / Q000037:antagonists & inhibitors / Q000097:blood; D009566:Nitrates / Q000037:antagonists & inhibitors / Q000097:blood; D009569:Nitric Oxide / Q000378:metabolism*; D009573:Nitrites / Q000037:antagonists & inhibitors / Q000097:blood; D009952:Ornithine / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D004791:Enzyme Inhibitors; D006146:Guanidines; D008070:Lipopolysaccharides; D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide; D008315:Malondialdehyde; D009952:Ornithine; C004479:pimagedine