Effect of endotoxin on circulating cyclic GMP in the rat.
The aim of this study was to investigate the possible use of plasmatic cyclic GMP as an index of L-arginine/nitric oxide (L-Arg/NO) pathway activation by E. coli endotoxin in vivo. Endotoxin (20 mg kg-1 i.p.) caused a time-dependent increase in plasmatic cyclic GMP in anaesthetised rats which corresponded with the time course of L-Arg/NO pathway activation in aortas from the same rats, but was not prevented by a specific inhibitor of this pathway, NG-nitro-L-arginine methyl ester (1 mg kg-1 or 20 mg kg-1 h-1 i.v.). Elevated plasmatic cyclic GMP was however also associated with an increased plasma concentration of atrial natriuretic peptide (ANP) in endotoxin-treated rats. We conclude that plasma cyclic GMP cannot be used as a direct marker of L-Arg/NO pathway activation by endotoxin but may instead be a reflection of an endotoxin-induced increase in plasma ANP activity.
Schuller
F
F
Laboratoire de Pharmacologie Cellulaire et Moléculaire, Université Louis Pasteur de Strasbourg, CNRS URA 600, Illkirch, France.
Fleming
I
I
Stoclet
J C
JC
Gray
G A
GA
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D009320:Atrial Natriuretic Factor / Q000097:blood; D006152:Cyclic GMP / Q000097:blood* / Q000378:metabolism; D004731:Endotoxins / Q000494:pharmacology*; D004926:Escherichia coli; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013895:Thoracic Arteries / Q000187:drug effects / Q000378:metabolism
D004731:Endotoxins; D009569:Nitric Oxide; D009320:Atrial Natriuretic Factor; D001120:Arginine; D006152:Cyclic GMP; D019331:NG-Nitroarginine Methyl Ester