title: Brief exposure to secondhand smoke reversibly impairs endothelial vasodilatory function.
abstract: BACKGROUND
  We sought to determine the effects of brief exposures to low concentrations of tobacco secondhand smoke (SHS) on arterial flow-mediated dilation (FMD, a nitric oxide-dependent measure of vascular endothelial function), in a controlled animal model never before exposed to smoke. In humans, SHS exposure for 30 min impairs FMD. It is important to gain a better understanding of the acute effects of exposure to SHS at low concentrations and for brief periods of time.
  
  
  METHODS
  We measured changes in FMD in rats exposed to a range of real-world levels of SHS for durations of 30 min, 10 min, 1 min, and 4 breaths (roughly 15 s).
  
  
  RESULTS
  We observed a dose-response relationship between SHS particle concentration over 30 min and post-exposure impairment of FMD, which was linear through the range typically encountered in smoky restaurants and then saturated at higher concentrations. One min of exposure to SHS at moderate concentrations was sufficient to impair FMD.
  
  
  CONCLUSIONS
  Brief SHS exposure at real-world levels reversibly impairs FMD. Even 1 min of SHS exposure can cause reduction of endothelial function.
authors.affiliation: Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA;
authors.forename: Kranthi
authors.initials: K
authors.lastname: Pinnamaneni
authors.forename: Richard E
authors.initials: RE
authors.lastname: Sievers
authors.forename: Rikki
authors.initials: R
authors.lastname: Sharma
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Selchau
authors.forename: Gustavo
authors.initials: G
authors.lastname: Gutierrez
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Nordsieck
authors.forename: Robert
authors.initials: R
authors.lastname: Su
authors.forename: Songtao
authors.initials: S
authors.lastname: An
authors.forename: Qiumei
authors.initials: Q
authors.lastname: Chen
authors.forename: Xiaoyin
authors.initials: X
authors.lastname: Wang
authors.forename: Ronak
authors.initials: R
authors.lastname: Derakhshandeh
authors.forename: Kirstin
authors.initials: K
authors.lastname: Aschbacher
authors.forename: Christian
authors.initials: C
authors.lastname: Heiss
authors.forename: Stanton A
authors.initials: SA
authors.lastname: Glantz
authors.forename: Suzaynn F
authors.initials: SF
authors.lastname: Schick
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Springer
mesh_terms: D000818:Animals; D004108:Dilatation, Pathologic; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000503:physiopathology*; D005260:Female; D005263:Femoral Artery / Q000503:physiopathology; D006801:Humans; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D014028:Tobacco Smoke Pollution