Relaxation of intrapulmonary artery and vein by nitrogen oxide-containing vasodilators and cyclic GMP

Journal Article · Sat Dec 31 23:00:00 EST 1983 · J. Pharmacol. Exp. Ther.; (United States)

OSTI ID:6748142

Edwards, J C; Ignarro, L J; Hyman, A L; Kadowitz, P J

The present study examines the relationship between tissue cyclic nucleotide levels and relaxation of bovine intrapulmonary arterial and venous smooth muscle in response to nitroglycerin, nitroprusside, S-nitroso-N-acetylpenicillamine and isoproterenol. Recent studies have suggested that cyclic GMP may be involved in the relaxation of vascular smooth muscle produced by nitrogen oxide-containing vasodilators and that S-nitrosothiols may act as intermediates of the latter agents. In the present study, nitroglycerin, nitroprusside and S-nitroso-N-acetylpenicillamine were more potent as relaxants of venous than arterial segments. Each of these agents elevated tissue cyclic GMP levels, but not cyclic AMP levels, before relaxation. These nitrogen oxide-containing agents were more potent as elevators of cyclic GMP levels in venous than arterial tissue and this correlated generally with their effects on vascular smooth muscle tone. Methylene blue antagonized both relaxation and increased cyclic GMP levels elicited by nitroglycerin, nitroprusside and S-nitroso-N-acetylpenicillamine. In contrast to the nitrogen oxide vasodilators, 8-bromo-cyclic GMP was equally effective in reducing induced tone in arterial or venous segments. Similarly, isoproterenol relaxed arterial and venous segments with equivalent sensitivities. Relaxation by isoproterenol was preceded by or occurred concomitantly with increased levels of cyclic AMP but not cyclic GMP and both effects were antagonized by propranolol. These findings are consistent with the hypothesis that vascular smooth muscle relaxation in response to nitrogen oxide-containing vasodilators or isoproterenol may be mediated or modulated by the intracellular accumulation of cyclic GMP or cyclic AMP, respectively.

• Research Organization: Tulane Univ., New Orleans, LA
• OSTI ID: 6748142
• Journal Information: J. Pharmacol. Exp. Ther.; (United States), Journal Name: J. Pharmacol. Exp. Ther.; (United States) Vol. 228:1; ISSN JPETA
• Country of Publication: United States
• Language: English

Related Subjects

560305* -- Chemicals Metabolism & Toxicology-- Vertebrates-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
AROMATICS
ARTERIES
AZAARENES
BIOLOGICAL EFFECTS
BIOLOGICAL PATHWAYS
BLOOD VESSELS
BODY
CARDIOVASCULAR AGENTS
CARDIOVASCULAR SYSTEM
CATTLE
CHALCOGENIDES
CHEMICAL EXPLOSIVES
DOMESTIC ANIMALS
DRUGS
ESTERS
EXPLOSIVES
GUANOSINE
HETEROCYCLIC COMPOUNDS
MAMMALS
MUSCLES
NITRIC ACID ESTERS
NITROGEN COMPOUNDS
NITROGEN OXIDES
NITROGLYCERIN
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
OXIDES
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
PURINES
RIBOSIDES
RUMINANTS
VASODILATION
VASODILATORS
VERTEBRATES