title: N-acetylcysteine enhances nitroglycerin-induced headache and cranial arterial responses.
abstract: The effects of N-acetylcysteine, a sulfhydryl group donor, on nitroglycerin-induced headache and dilation of temporal and radial arteries were investigated in 11 healthy volunteers. Nitroglycerin, 0.06 microgram/kg/min, was infused for 20 minutes immediately after and 120 minutes after pretreatment with N-acetylcysteine (100 mg/kg) or placebo. Arterial diameters were measured with high frequency ultrasound, and pain was scored by use of a previously evaluated 10-point scale. Plasma levels of free (n = 2) and total (n = 11) N-acetylcysteine were determined. N-Acetylcysteine potentiated the headache response (median headache score, 3 versus 1), and the headache retained its vascular characteristics. Temporal artery dilation was also potentiated by N-acetylcysteine, 139% +/- 3% versus 127% +/- 3% of baseline, whereas the radial artery was unaffected. The potentiation was most pronounced after the first nitroglycerin infusion (12% versus 4.5% compared with placebo). A prolonged dilation of the temporal artery was observed only after the first nitroglycerin infusion, when high levels of N-acetylcysteine were present.
authors.affiliation: Department of Neurology, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
authors.forename: H K
authors.initials: HK
authors.lastname: Iversen
mesh_terms: D000111:Acetylcysteine / Q000009:adverse effects / Q000097:blood / Q000494:pharmacology*; D000328:Adult; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004357:Drug Synergism; D005260:Female; D005542:Forearm / Q000098:blood supply; D006261:Headache / Q000139:chemically induced*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D005996:Nitroglycerin; D012886:Skull / Q000098:blood supply*; D013699:Temporal Arteries / Q000187:drug effects; D013997:Time Factors; D014664:Vasodilation / Q000187:drug effects
chemical_list: D005996:Nitroglycerin; D000111:Acetylcysteine