Cationic amino acids inhibit the effects of L-arginine in rat aorta exposed to lipopolysaccharide.
The effects of L-arginine (10(-7) to 10(-2) M), L-lysine and L-ornithine were examined in endothelium-denuded rat aortic rings preincubated 4 h with lipopolysaccharide (10 micrograms/ml) and contracted with noradrenaline (3 microM). L-Lysine (10 mM) and L-ornithine (10-30 mM) slightly increased contraction and caused a rightward shift in concentration-relaxation curves in response to L-arginine. These cationic amino acids may compete with L-arginine for the lipopolysaccharide-induced NO-synthase or the amino acid transporter, or both.
Schott
C A
CA
Université Louis Pasteur de Strasbourg, Laboratoire de Pharmacologie Cellulaire et Moléculaire-CNRS URA600, Illkirch, France.
Vetrovsky
P
P
Stoclet
J C
JC
D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D001011:Aorta / Q000187:drug effects; D001120:Arginine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000502:physiology; D066298:In Vitro Techniques; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008239:Lysine / Q000494:pharmacology; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009952:Ornithine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar
D000596:Amino Acids; D008070:Lipopolysaccharides; D001120:Arginine; D009952:Ornithine; D008239:Lysine