title: Physiological role of nitric oxide in oxygen consumption by arteriolar wall.
abstract: To study the role of nitric oxide (NO) in regulating oxygen consumption by vessel walls, the oxygen consumption rate of arteriolar walls in rat cremaster muscle was measured in vivo during flow-induced vasodilation and after inhibiting NO synthesis. The oxygen consumption rate of arteriolar walls was calculated based on the intra- and peri-vascular oxygen tension (PO(2)) values measured by phosphorescence quenching laser microscopy. The peri-vascular PO(2) value of the arterioles during vasodilation was significantly higher than under control conditions, although the intravascular PO(2) values under both conditions were approximately the same. On the other hand, inhibition of NO synthesis caused a significant decrease in both the intra- and peri-vascular PO(2) values of the arterioles. The inhibition of NO synthesis increased the oxygen consumption rate of the vessel walls by 42%, whereas enhancement of flow-induced NO release decreased it by 34%. These results suggest that NO plays an important role not only as a regulator of peripheral vascular tone, but also as a modulator of tissue oxygen consumption by reducing oxygen consumption by vessel walls.
authors.affiliation: Department Bioscience and Engineering, Shibaura Institute of Technology, Saitama, Japan. shibatam@sic.shibaura-it.ac.jp
authors.forename: Masahiro
authors.initials: M
authors.lastname: Shibata
authors.forename: Takehiro
authors.initials: T
authors.lastname: Yamakoshi
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Yamakoshi
mesh_terms: D000818:Animals; D001160:Arterioles / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D018482:Muscle, Skeletal / Q000098:blood supply / Q000187:drug effects / Q000502:physiology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000037:antagonists & inhibitors / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D010100:Oxygen / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D014664:Vasodilation / Q000187:drug effects
chemical_list: D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D010100:Oxygen; D019331:NG-Nitroarginine Methyl Ester