BACKGROUND: Arterial stiffness is an important determinant of cardiovascular risk. Several lines of evidence support a role for the endothelium in regulating arterial stiffness by release of vasoactive mediators. We hypothesized that @entity842 (NO) acting locally regulates arterial stiffness in vivo, and the aim of this experiment was to test this hypothesis in an ovine hind-limb preparation. METHODS AND RESULTS: All studies were conducted in anesthetized @entity742 . Pulse wave velocity ( @entity122 ) was calculated by the foot-to-foot methodology from 2 pressure waveforms recorded simultaneously with a high-fidelity dual pressure-sensing catheter placed in the common iliac artery. Intra-arterial infusion of @entity7293 ( @entity7293 ) increased iliac @entity122 significantly, by 3+/-2% (P<0.01). Infusion of @entity934 and @entity1242 reduced @entity122 significantly, by 6+/-4% (P=0.03) and 5+/-2% (P<0.01), respectively. Only the effect of @entity934 , however, was significantly inhibited during coinfusion of @entity7293 (P=0.03). There was no change in systemic arterial pressure throughout the studies. Importantly, infusion of @entity7293 or @entity934 distal to the common iliac artery (via the sheath) did not affect @entity122 . CONCLUSIONS: These results demonstrate, for the first time, that basal NO production influences large-artery distensibility. In addition, exogenous @entity934 and @entity1242 both increase arterial distensibility, the former mainly through NO production. This may help explain why conditions that exhibit @entity409 are also associated with increased arterial stiffness. Therefore, reversal of @entity409 or drugs that are large-artery vasorelaxants may be effective in reducing large-artery stiffness in @entity1 , and thus cardiovascular risk.

XXXX regulates local arterial distensibility in vivo.

@entity1 :: ('9606', 'Species') :: ['humans'] @entity742 :: ('9940', 'Species') :: ['sheep'] @entity1242 :: ('MESH:D005996', 'Chemical') :: ['glyceryl trinitrate'] @entity409 :: ('MESH:D008107', 'Disease') :: ['endothelial dysfunction'] @entity7293 :: ('CHEBI:28229', 'Chemical') :: ['L-NMMA', 'N(G)-monomethyl-L-arginine'] @entity842 :: ('MESH:D009569', 'Chemical') :: ['nitric oxide'] @entity122 :: ('31732', 'Species') :: ['PWV'] @entity934 :: ('MESH:D000109', 'Chemical') :: ['acetylcholine']
@entity842 :: (MESH:D009569,Chemical) :: ['Nitric oxide']
