title: Headache and prolonged dilatation of the middle meningeal artery by PACAP38 in healthy volunteers.
abstract: OBJECTIVE
  To explore a possible relationship between vasodilatation and delayed headache we examined the effect of pituitary adenylate cyclase-activating polypeptide-38 (PACAP38) on the middle meningeal artery (MMA) and middle cerebral artery (MCA) using high resolution magnetic resonance angiography (MRA).
  
  
  METHODS
  In a double-blind, randomized, placebo-controlled study 14 healthy volunteers were scanned repeatedly after infusion (20 min) of 10 pmol/kg/min PACAP38 or placebo. In addition, four participants were scanned following subcutaneous sumatriptan (6 mg).
  
  
  RESULTS
  We found significant dilatation of the MMA (p = 0.00001), but not of the MCA (p = 0.50) after PACAP38. There was no change after placebo (p > 0.40). Vasodilatation (range 16-23%) lasted more than 5 h. Sumatriptan selectively contracted the MMA by 12.3% (p = 0.043).
  
  
  CONCLUSIONS
  PACAP38-induced headache is associated with prolonged dilatation of the MMA but not of the MCA. Sumatriptan relieves headache in parallel with contraction of the MMA but not of the MCA.
authors.affiliation: University of Copenhagen, Denmark.
authors.forename: Faisal Mohammad
authors.initials: FM
authors.lastname: Amin
authors.forename: Mohammad Sohail
authors.initials: MS
authors.lastname: Asghar
authors.forename: Song
authors.initials: S
authors.lastname: Guo
authors.forename: Anders
authors.initials: A
authors.lastname: Hougaard
authors.forename: Adam Espe
authors.initials: AE
authors.lastname: Hansen
authors.forename: Henrik Winther
authors.initials: HW
authors.lastname: Schytz
authors.forename: Rob J
authors.initials: RJ
authors.lastname: van der Geest
authors.forename: Patrick Jh
authors.initials: PJ
authors.lastname: de Koning
authors.forename: Henrik Bw
authors.initials: HB
authors.lastname: Larsson
authors.forename: Jes
authors.initials: J
authors.lastname: Olesen
authors.forename: Messoud
authors.initials: M
authors.lastname: Ashina
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000378:metabolism; D005260:Female; D006261:Headache / Q000139:chemically induced* / Q000188:drug therapy / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008576:Meningeal Arteries / Q000187:drug effects* / Q000502:physiology; D020768:Middle Cerebral Artery / Q000187:drug effects / Q000502:physiology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000009:adverse effects*; D010919:Placebos; D018170:Sumatriptan / Q000008:administration & dosage; D013997:Time Factors; D014662:Vasoconstrictor Agents / Q000008:administration & dosage; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000009:adverse effects; D055815:Young Adult
chemical_list: D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D010919:Placebos; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D002245:Carbon Dioxide; D018170:Sumatriptan