title: Dipyrone attenuates cerebral vasospasm after experimental subarachnoid hemorrhage in rabbits.
abstract: BACKGROUND
  The purpose of this study was to evaluate the effect of the systemic administration of dipyrone in a triple subarachnoid hemorrhage (SAH) model of cerebral vasospasm in rabbits.
  
  
  METHODS
  Experimental subarachnoid hemorrhage was induced in rabbits by injecting autologous arterial blood into the cisterna magna. Digital subtraction angiographies (DSA) were performed before and after the first experimental SAH, and at 30, 45, 60 minutes and 72 hours after the first drug administration to measure the diameter of basilar artery. Intracisternal blood injections were repeated 24 and 48 hours after the first injection. Dipyrone (N.=20) or 0.9% NaCl (N.=20) was administered intravenously after initial SAH induction and repeated at 8-hour intervals intramuscularly. After sacrificing by perfusion-fixation, basilar arteries were removed and sectioned for transmission electron microscopic (TEM) examination.
  
  
  RESULTS
  The average basilar artery diameter measured by DSA was 724±19 μm in the control, and 686±29 μm in treatment group before SAH. After SAH, mean basilar artery diameters decreased to 71% and 68% of their basal values, respectively. Dipyrone significantly attenuated the basilar artery diameter at one and 72 hours after the first drug administration, in comparison to the control group. TEM studies showed more edema in the endothelial cells of the basilar arteries of the control group when compared to the treatment group.
  
  
  CONCLUSIONS
  Dipyrone showed a beneficial effect in autologous blood-induced basilar artery vasospasm in rabbits. These data support the idea that dipyrone can be a potential candidate drug to be tested in patients suffering from cerebral vasospasm secondary to subarachnoid hemorrhage.
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Medipol University, Istanbul, Turkey - gsilav@yahoo.com.
authors.forename: Gökalp
authors.initials: G
authors.lastname: Silav
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Ankara University, Ankara, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Ergün
authors.affiliation: Department of Neurosurgery, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey.
authors.forename: Habibullah
authors.initials: H
authors.lastname: Dolgun
authors.affiliation: Department of Radiology, Faculty of Medicine, Ankara University, Ankara, Turkey.
authors.forename: Tanzer
authors.initials: T
authors.lastname: Sancak
authors.affiliation: Department of Anatomy, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Mustafa F
authors.initials: MF
authors.lastname: Sargon
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Ankara University, Ankara, Turkey.
authors.forename: Nihat
authors.initials: N
authors.lastname: Egemen
mesh_terms: D015901:Angiography, Digital Subtraction; D000818:Animals; D004177:Dipyrone / Q000008:administration & dosage / Q000494:pharmacology*; D004195:Disease Models, Animal; D011817:Rabbits; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging / Q000188:drug therapy*; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology*; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging / Q000188:drug therapy*
chemical_list: D014665:Vasodilator Agents; D004177:Dipyrone