title: Characterization of spinal subarachnoid bleeding associated to graded traumatic spinal cord injury in the rat.
abstract: METHODS
  Observational study in rats subjected to traumatic spinal cord injury (SCI).
  
  
  OBJECTIVE
  To describe the features of spinal subarachnoid bleeding (SSB) occurring after graded SCI. SSB after SCI has been reported previously, but has not been studied systematically despite the fact that cerebral subarachnoid bleeding often produces severe neurological damage.
  
  
  METHODS
  Mexico.
  
  
  METHODS
  Anesthetized rats were subjected to mild or severe spinal cord contusion at T9. Occurrence, size, progression and location of SSB were characterized morphologically and scored from T7-T12 at 1 h and 1, 3 and 7 days post injury. Besides, contusions were videotaped to visualize bleeding at the moment of impact.
  
  
  RESULTS
  SSB started immediately after contusion (severe or mild) and decreased gradually over time. For all vertebral segments, at all time points examined by histology, 48% of areas scored after severe contusion showed bleeding: 25% minor, 17% moderate and 6% major. After mild contusion, only 15% showed bleeding: 13 minor and 2% moderate. Maximum bleeding occurred early after injury in dorsal area of the epicenter in 100% of severe contusions (6% minor, 38 moderate and 56% major), and in 69% of mild contusions (63 minor and 6% moderate).
  
  
  CONCLUSIONS
  Here, we detail SSB patterns occurring after graded SCI. Further studies are warranted to elucidate the possible role extramedullary events, such as SSB, in the pathophysiology of SCI that might encourage the development of new strategies for its management.
authors.affiliation: 1] Research Unit for Neurological Diseases, Instituto Mexicano del Seguro Social (IMSS), Mexico City, Mexico [2] Department of Neurology, School of Veterinary Medicine, Universidad Autónoma del Estado de Mexico, Toluca, Mexico.
authors.forename: H J
authors.initials: HJ
authors.lastname: Reyes-Alva
authors.affiliation: 1] Department of Experimental Surgery, Proyecto Camina A.C., Mexico City, Mexico [2] Department of Biochemistry, Instituto Nacional de Rehabilitación, Mexico City, Mexico.
authors.forename: R E
authors.initials: RE
authors.lastname: Franco-Bourland
authors.affiliation: Department of Experimental Surgery, Proyecto Camina A.C., Mexico City, Mexico.
authors.forename: A
authors.initials: A
authors.lastname: Martinez-Cruz
authors.affiliation: 1] Research Unit for Neurological Diseases, Instituto Mexicano del Seguro Social (IMSS), Mexico City, Mexico [2] Department of Experimental Surgery, Proyecto Camina A.C., Mexico City, Mexico.
authors.forename: I
authors.initials: I
authors.lastname: Grijalva
authors.affiliation: 1] Research Unit for Neurological Diseases, Instituto Mexicano del Seguro Social (IMSS), Mexico City, Mexico [2] Department of Experimental Surgery, Proyecto Camina A.C., Mexico City, Mexico.
authors.forename: I
authors.initials: I
authors.lastname: Madrazo
authors.affiliation: 1] Research Unit for Neurological Diseases, Instituto Mexicano del Seguro Social (IMSS), Mexico City, Mexico [2] Department of Experimental Surgery, Proyecto Camina A.C., Mexico City, Mexico.
authors.forename: G
authors.initials: G
authors.lastname: Guizar-Sahagun
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D020318:Rats, Long-Evans; D012720:Severity of Illness Index; D013119:Spinal Cord Injuries / Q000150:complications / Q000473:pathology* / Q000503:physiopathology*; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000473:pathology* / Q000503:physiopathology*; D013904:Thoracic Vertebrae; D013997:Time Factors; D014741:Video Recording