Heterogeneity in endothelium-derived nitric oxide-mediated relaxation of different sized pulmonary arteries of newborn lambs.

Détails

ID Serval
serval:BIB_53CB284C2D99
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Heterogeneity in endothelium-derived nitric oxide-mediated relaxation of different sized pulmonary arteries of newborn lambs.
Périodique
Pediatric research
Auteur⸱e⸱s
Gao Y., Tolsa J.F., Raj J.U.
ISSN
0031-3998
Statut éditorial
Publié
Date de publication
1998
Peer-reviewed
Oui
Volume
44
Numéro
5
Pages
723-9
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S. - Publication Status: ppublish
Résumé
Endothelium-derived nitric oxide (EDNO) plays a pivotal role in regulating pulmonary circulation. To determine whether there is a heterogeneity in EDNO-mediated responses of different sized pulmonary vessels, we studied small and large isolated pulmonary arteries of newborn lambs (diameter, 0.4-0.7 and 1.5-2.5 mm, respectively). The isometric tension of vessel rings were recorded while suspended in organ chambers filled with modified Krebs-Ringer bicarbonate solution (95% O2-5% CO2, 37 degrees C). In vessels preconstricted with norepinephrine, acetylcholine and bradykinin induced a greater relaxation of small pulmonary arteries than of large pulmonary arteries. Acetylcholine, bradykinin, and nitric oxide also induced a greater increase in cGMP content in small arteries than in large ones. The responses to acetylcholine and bradykinin were endothelium-dependent and inhibited by nitro-L-arginine, an inhibitor of nitric oxide synthase. In vessels without endothelium, the response to nitric oxide was inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of soluble guanylate cyclase. The activity of soluble guanylyl cyclase of small arteries was greater than that of large arteries under basal conditions and after stimulation with S-nitroso-N-acetylpenicillamine, a nitric oxide donor. These results demonstrate that heterogeneity exists in EDNO-mediated relaxation of small and large pulmonary arteries in newborn lambs. A difference in the soluble guanylate cyclase activity of vascular smooth muscle may have contributed to this phenomenon.
Mots-clé
Acetylcholine, Animals, Bradykinin, Cyclic GMP, Endothelium, Vascular, Female, Male, Nitric Oxide, Nitric Oxide Synthase, Nitric Oxide Synthase Type III, Penicillamine, Pulmonary Artery, S-Nitroso-N-Acetylpenicillamine, Sheep, Vasodilation
Pubmed
Web of science
Open Access
Oui
Création de la notice
28/01/2008 13:52
Dernière modification de la notice
20/08/2019 14:08
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