title: Impacts of pulsatile systemic circulation on endothelium-derived nitric oxide release in anesthetized dogs.
abstract: BACKGROUND
  The effects of pulsatile flow on endothelium-derived nitric oxide-mediated vasodilation are not fully elucidated in an in vivo model.
  
  
  METHODS
  A left ventricular assist device was established in 10 anesthetized dogs with a centrifugal pump and an air-driven pneumatic pump. The systemic circulation was subjected to step changes in the frequency of pulse (0, 30, 60, and 120 bpm with a fixed pulse pressure of 50 mm Hg), and in the amplitude of pulse (0, 20, and 50 mm Hg with a fixed pulse rate of 120 bpm). Hemodynamic variables and calculated total systemic vascular resistance were compared before and after the administration of N(G)-Nitro-L-arginine Methyl Ester (L-NAME) (20 mg/kg). Plasma NO2-/NO3- concentration levels were also measured.
  
  
  RESULTS
  Total systemic vascular resistance significantly decreased while plasma NO2-/No3- concentration increased in response to the rise in both pulse rate and pulse pressure. However, L-NAME significantly diminished these effects of pulsatile flow.
  
  
  CONCLUSIONS
  Both the frequency and the amplitude of pulse wave in the systemic circulation are significant independent stimuli for endothelium-derived nitric oxide-mediated vasodilation in vivo.
authors.affiliation: Division of Cardiovascular Surgery, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nakano
authors.forename: R
authors.initials: R
authors.lastname: Tominaga
authors.forename: S
authors.initials: S
authors.lastname: Morita
authors.forename: M
authors.initials: M
authors.lastname: Masuda
authors.forename: I
authors.initials: I
authors.lastname: Nagano
authors.forename: K
authors.initials: K
authors.lastname: Imasaka
authors.forename: H
authors.initials: H
authors.lastname: Yasui
mesh_terms: D000818:Animals; D004285:Dogs; D004730:Endothelium, Vascular / Q000503:physiopathology*; D006353:Heart-Assist Devices; D006439:Hemodynamics / Q000502:physiology; D009569:Nitric Oxide / Q000097:blood*; D011673:Pulsatile Flow / Q000502:physiology*; D014655:Vascular Resistance / Q000502:physiology
chemical_list: D009569:Nitric Oxide