title: A single bout of moderate-intensity exercise increases vascular NO bioavailability and attenuates adrenergic receptor-dependent and -independent vasoconstrictor response in rat aorta.
abstract: The present study investigated the effect of one bout of moderate-intensity exercise on the adrenergic receptor-dependent and -independent vasoconstrictor response in rat aortas, and the role of nitric oxide (NO) bioavailability on these vasomotor responses. One group of rats was submitted to a 60 min of exercise at approximately 60% of maximal exercise capacity on a treadmill (exercise group) and the other one was placed in the treadmill without running (control group). Immediately after this period, both groups were euthanized and the thoracic aorta was removed to evaluate the vasoconstrictor response to norepinephrine and potassium chloride, and to evaluate the vascular nitrite and nitrate concentration. One bout of exercise attenuated the maximal contractile response to both norepinephrine and potassium chloride compared to control group. These differences on vascular reactivity were not observed in endothelium-denuded aortic rings and aortic rings pre-incubated with a nitric oxide synthesis inhibitor. Additionally, exercise group increased NO bioavailability (nitrite and nitrate concentration) as compared to control group. These results demonstrate that one bout of moderate-intensity exercise is able to attenuate adrenergic receptor-dependent and -independent vasoconstrictor response in rat aorta, mainly by increasing vascular NO bioavailability.
authors.affiliation: School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil.
authors.forename: Luiz Roberto Grassmann
authors.initials: LR
authors.lastname: Bechara
authors.forename: Leonardo Yuji
authors.initials: LY
authors.lastname: Tanaka
authors.forename: Adriana Marques dos
authors.initials: AM
authors.lastname: Santos
authors.forename: Camila Paixão
authors.initials: CP
authors.lastname: Jordão
authors.forename: Luise Gustavo Oliveira de
authors.initials: LG
authors.lastname: Sousa
authors.forename: Teresa
authors.initials: T
authors.lastname: Bartholomeu
authors.forename: Paulo Rizzo
authors.initials: PR
authors.lastname: Ramires
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000378:metabolism*; D001682:Biological Availability; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000378:metabolism*; D008297:Male; D023421:Models, Animal; D009569:Nitric Oxide / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011941:Receptors, Adrenergic / Q000378:metabolism*; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology*
chemical_list: D011941:Receptors, Adrenergic; D009569:Nitric Oxide; D011189:Potassium Chloride; D009638:Norepinephrine