title: Closed head injury in rats: histopathological aspects in an experimental weight drop model.
abstract: OBJECTIVE
  To study histopathological findings due to a model of closed head injury by weight loss in rats.
  
  
  METHODS
  A platform was used to induce closed cranial lesion controlled by weight loss with a known and predefined energy. 25 male Wistar rats (Rattus novergicus albinus) were divided in five equal groups which received different cranial impact energy levels: G1, G2, G3 and G4 with 0.234J, 0.5J, 0.762J and 1J respectively and G5 (Sham). Under the effect of analgesia, the brain of each group was collected and prepared for histopathological analysis by conventional optic microscopy.
  
  
  RESULTS
  It was observed greater number of injured neurons in animals of group 4, however neuronal death also could be noticed in animals of group 5. Intraparenchymal hemorrhages were more frequent in animals of group 4 and the cytotoxic brain swelling and vascular congestion were more intense in this group
  
  
  CONCLUSIONS
  The histopathological analysis of these findings allowed to observe typical cranial trauma alterations and these keep close relation with impact energy.
authors.affiliation: Faculty of Medicine, UESPI, Piaui, Brazil.
authors.forename: Danilo dos Santos
authors.initials: Ddos S
authors.lastname: Silva
authors.forename: José Nazareno Pearce de Oliveira
authors.initials: JN
authors.lastname: Brito
authors.forename: Jerúsia Oliveira
authors.initials: JO
authors.lastname: Ibiapina
authors.forename: Marcel Fernando Miranda Batista
authors.initials: MF
authors.lastname: Lima
authors.forename: Andréa Ribeiro Gonçalves de Vasconcelos
authors.initials: AR
authors.lastname: Medeiros
authors.forename: Bárbara Hamedy Carvalho e
authors.initials: BH
authors.lastname: Queiroz
authors.forename: Aline Lariessy Campos
authors.initials: AL
authors.lastname: Paiva
authors.forename: Vanessa Olímpio de Melo
authors.initials: VO
authors.lastname: Guedes
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D016489:Head Injuries, Closed / Q000150:complications / Q000473:pathology*; D008297:Male; D009474:Neurons / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D015599:Trauma Severity Indices