Nonselective versus selective inhibition of inducible nitric oxide synthase in experimental endotoxic shock.
The effects of two nitric oxide synthase (NOS) inhibitors with different isoform selectivity were compared in a murine model of endotoxemia. Mice challenged with 70 mg/kg intraperitoneal (ip) lipopolysaccharide (LPS) were treated 6 h after LPS with either NG-gamma-L-arginine methyl ester (L-NAME, nonselective NOS inhibitor, 10-60 mg/kg), L-canavanine (selective inhibitor of inducible NOS, 50-300 mg/kg), or saline (0.2 mL) given ip. In a subset of mice, plasma concentrations of nitrate (NO breakdown product), lipase (pancreas injury), lactate dehydrogenase, and transaminases (liver injury) were measured 16 h after LPS. Although both inhibitors reduced plasma nitrate, they produced contrasting effects on survival and organ injury. L-NAME enhanced liver damage and tended to accelerate the time of death, while L-canavanine significantly reduced mortality and had no deleterious effects in terms of organ damage. These results indicate that nonselective NOS inhibitors are detrimental in endotoxic shock and support the potential usefulness of selective inducible NOS inhibitors in this setting.
Liaudet
L
L
Institute of Pathophysiology, Department of Internal Medicine, University Hospital, Lausanne, Switzerland.
Rosselet
A
A
Schaller
M D
MD
Markert
M
M
Perret
C
C
Feihl
F
F
D000818:Animals; D002172:Canavanine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D007770:L-Lactate Dehydrogenase / Q000032:analysis / Q000097:blood; D008049:Lipase / Q000032:analysis / Q000097:blood; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000494:pharmacology; D008099:Liver / Q000473:pathology; D051379:Mice; D019331:NG-Nitroarginine Methyl Ester / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D009566:Nitrates / Q000032:analysis / Q000097:blood; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D012772:Shock, Septic / Q000188:drug therapy* / Q000378:metabolism*; D000637:Transaminases / Q000032:analysis / Q000097:blood
D004791:Enzyme Inhibitors; D008070:Lipopolysaccharides; D009566:Nitrates; D009569:Nitric Oxide; D002172:Canavanine; D007770:L-Lactate Dehydrogenase; D019001:Nitric Oxide Synthase; D000637:Transaminases; D008049:Lipase; D019331:NG-Nitroarginine Methyl Ester