title: Acute effect of sidestream cigarette smoke extract on vascular endothelial function.
abstract: Acute exposure to passive smoking adversely affects vascular function by promoting oxidative stress and endothelial dysfunction. However, it is not known whether tobacco sidestream (SS) smoke has a greater deleterious effect on the endothelium than non-tobacco SS smoke and whether these effects are related to nicotinic endothelial stimulation. To test these hypotheses, endothelial-dependent relaxation and superoxide anion production were assessed in isolated rat aortas incubated with tobacco SS smoke, non-tobacco SS smoke, or pure nicotine. Tobacco SS smoke decreased the maximal relaxation to acetylcholine (Ach) from 79 +/- 6% to 57 +/- 7.3% (% inhibition of phenylephrine-induced plateau, P < 0.001) and increased superoxide anion production from 31 +/- 9.7 to 116 +/- 24 count/10 sec/mg (P < 0.01, lucigenin-enhanced chemiluminescence technique). The non-tobacco SS smoke extract had no significant effect on the response to Ach but increased superoxide anion production in the aortic wall to 133 +/- 2 count/10 sec/mg (P < 0.001). Furthermore, concentration-response curves to Ach and superoxide production remained unaltered with nicotine (0.001, 0.01, or 0.1 mM). In conclusion, despite similar increases in vascular wall superoxide production with tobacco and non-tobacco SS smoke, only the tobacco SS smoke extracts affected endothelium-dependent vasorelaxation. Nicotine alone does not reproduce the effects seen with tobacco SS smoke, suggesting that the acute endothelial toxicity of passive smoking cannot simply be ascribed to a nicotine-dependent mechanism.
authors.affiliation: Department of Cardiology, Erasme Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium. jfxa@skynet.be
authors.forename: J F
authors.initials: JF
authors.lastname: Argacha
authors.forename: D
authors.initials: D
authors.lastname: Fontaine
authors.forename: D
authors.initials: D
authors.lastname: Adamopoulos
authors.forename: A
authors.initials: A
authors.lastname: Ajose
authors.forename: P
authors.initials: P
authors.lastname: van de Borne
authors.forename: J
authors.initials: J
authors.lastname: Fontaine
authors.forename: G
authors.initials: G
authors.lastname: Berkenboom
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009538:Nicotine / Q000008:administration & dosage / Q000009:adverse effects*; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D012906:Smoke / Q000009:adverse effects*; D013481:Superoxides / Q000378:metabolism; D014028:Tobacco Smoke Pollution / Q000009:adverse effects; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000494:pharmacology; D014026:Nicotiana
chemical_list: D012906:Smoke; D014028:Tobacco Smoke Pollution; D014665:Vasodilator Agents; D013481:Superoxides; D009538:Nicotine; D000109:Acetylcholine