title: Local versus systemic influences on uterine vascular reactivity during pregnancy in the single-horn gravid rat.
abstract: This study was conducted to determine whether gestational changes in maternal uterine artery reactivity are primarily driven by local vs. systemic factors. Rats underwent surgical ligation of one oviduct, thereby restricting implantation and pregnancy to one uterine horn while maintaining a gestational endocrine milieu. Uterine arcuate arteries were isolated and cannulated to evaluate reactivity. Vessels from the implanted horn were significantly more sensitive to phenylephrine and less sensitive to sodium nitroprusside than those from the non-implanted horn; endothelial basal calcium levels were only increased in the implanted horn. Conversely, there were no differences in sensitivity to acetylcholine, or its effects on endothelial cell calcium, although efficacy was greater in vessels from the implanted vs. non-implanted horn. These findings demonstrate that local factors are predominant in inducing changes in vascular smooth muscle function, while endothelial adaptations result from an interplay between local and systemic factors, with distinct effects attributable to each.
authors.affiliation: Department of Obstetrics and Gynecology and Reproductive Sciences, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Fuller
authors.forename: Ilsley
authors.initials: I
authors.lastname: Colton
authors.forename: Natalia
authors.initials: N
authors.lastname: Gokina
authors.forename: Maurizio
authors.initials: M
authors.lastname: Mandala
authors.forename: George
authors.initials: G
authors.lastname: Osol
mesh_terms: D000818:Animals; D005260:Female; D009131:Muscle, Smooth, Vascular / Q000502:physiology*; D009599:Nitroprusside / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D055988:Uterine Artery / Q000502:physiology*; D014599:Uterus / Q000098:blood supply*; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D010656:Phenylephrine