title: Transient middle cerebral artery occlusion in rats as an experimental model of brain ischemia.
abstract: OBJECTIVE
  To assess a rat model of cerebral ischemia induced by occlusion of the middle cerebral artery and its effect on the area of cerebral infarction.
  
  
  METHODS
  Brain ischemia was induced in 52 male Wistar rats by introduction of a 3-0 nylon suture into the middle cerebral artery for either 90 (n=28) or 120 (n=24) minutes. Ischemic injury volume was determined by TTC staining, digital photography and analysis with the Image J software. Statistical analysis employed Student's t test and the Mann-Whitney U test.
  
  
  RESULTS
  The groups were similar in terms of weight (p=0.59). The length of thread inserted was 14.7 mm in the 90 min group and 20.2 mm in the 120 min group (p=0.37). Ischemic injury was detected in 11 animals (39%) after 90 min and 11 (45%) after 120 min (p=0.77). In animals exhibiting injury, filament length was 16.1 ± 11 mm (90 min) vs. 21.9 ± 7.4 mm (120 min) (p=0.15). The mean infarction zone volume was greater after 120 (259.2 mm³) than after 90 min (162.9 mm³) (p=0.04). The neurological deficit score for the 90 and 120 min groups was 2.0 and 2.4, respectively (p=0.84).
  
  
  CONCLUSIONS
  The experimental model induced significant ischemic cerebral injury in both groups.
authors.affiliation: Department of Clinical Surgery, UCS, Caxias do Sul, Brazil. rcalloni@terra.com.br
authors.forename: Renato Luis
authors.initials: RL
authors.lastname: Calloni
authors.forename: Bruno Costamilam
authors.initials: BC
authors.lastname: Winkler
authors.forename: Guilherme
authors.initials: G
authors.lastname: Ricci
authors.forename: Marcos Giacomelli
authors.initials: MG
authors.lastname: Poletto
authors.forename: Wagner Martins
authors.initials: WM
authors.lastname: Homero
authors.forename: Eduardo Pretto
authors.initials: EP
authors.lastname: Serafini
authors.forename: Oly Campos
authors.initials: OC
authors.lastname: Corleta
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000209:etiology / Q000473:pathology; D004195:Disease Models, Animal; D008297:Male; D020768:Middle Cerebral Artery / Q000601:surgery*; D009460:Neurologic Examination; D051381:Rats; D017208:Rats, Wistar; D018709:Statistics, Nonparametric; D013537:Sutures; D013997:Time Factors