title: [Effect of aminoguanidine on spinal cord edema of acute spinal cord injury in rats].
abstract: OBJECTIVE
  Aminoguanidine (AG) can reduce brain edema and increase the recovery of neuron functions in surgical brain injury and stroke. To investigate the effect of AG on spinal cord injury (SCI) in rats and its mechanism.
  
  
  METHODS
  A total of 150 adult male Sprague Dawley rats (weighing, 230-255 g) were divided into control group (group A, 25 rats without treatment), the sham-operated group (group B, 25 rats undergoing laminectomy), SCI group (group C, 25 SCI rats with injection of 5% DMSO), SCI + AG groups (groups D, E, and F, 25 SCI rats and AG injection of 75, 150, and 300 mg/kg, respectively). The optimal dosage of AG was screened by dry-wet weight method with the percentage of water content at 0, 12, 24, and 48 hours after injury. The blood-spinal cord barriar permeability was further detected by Evans blue (EB) method, aquaporins 4 (AQP4) mRNA expression by RT-PCR, AQP4 protein expression by immunohistochemistry and Western blot.
  
  
  RESULTS
  AG injection at dosage of 150 mg/kg can significantly reduce edema of spinal cords at 12, 24, and 48 hours after SCI (P < 0.05), so 150 mg/kg was the optimal dosage. The EB content in group E was significantly lower than that in group C at 12, 24, and 48 hours after SCI, and the permeability of blood-spinal cord barrier was significantly decreased compared with group C (P < 0.05). The AQP4 mRNA expressions in groups B and E were significantly lower than that in group C at 12, 24, and 48 hours after SCI (P < 0.05). AQP4 protein expressions in groups B and E were significantly lower than that in group C at 24 and 48 hours after SCI (P < 0.05) by Western blot. Immunohistochemical staining revealed that AQP4 protein expression in group C was significantly higher than that in groups B and E (P < 0.05) at 48 hours after SCI, but no significant difference was found between group B and group E (P > 0.05).
  
  
  CONCLUSIONS
  AG injection at dosage of 150 mg/kg can induce spinal cord edema and injury in rats, which could be correlated with the down-regulation of AQP4 expression.
authors.affiliation: Department of Orthopedics, First Affiliated Hospital, Liaoning Medical College, Jinzhou Liaoning 121001, PR China.
authors.forename: Zhongkai
authors.initials: Z
authors.lastname: Fan
authors.forename: Yang
authors.initials: Y
authors.lastname: Cao
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yansong
authors.initials: Y
authors.lastname: Wang
authors.forename: Deshui
authors.initials: D
authors.lastname: Yu
authors.forename: Mingchao
authors.initials: M
authors.lastname: Zhang
authors.forename: Xifan
authors.initials: X
authors.lastname: Mei
authors.forename: Gang
authors.initials: G
authors.lastname: Lü
mesh_terms: D000208:Acute Disease; D000818:Animals; D051401:Aquaporin 4 / Q000235:genetics / Q000378:metabolism*; D001812:Blood-Brain Barrier / Q000187:drug effects / Q000378:metabolism; D015153:Blotting, Western; D004195:Disease Models, Animal; D015536:Down-Regulation; D004487:Edema / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D006146:Guanidines / Q000008:administration & dosage / Q000627:therapeutic use*; D007150:Immunohistochemistry; D007274:Injections, Intraperitoneal; D008297:Male; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D010539:Permeability; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000378:metabolism / Q000473:pathology; D013119:Spinal Cord Injuries / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism
chemical_list: C496032:Aqp4 protein, rat; D051401:Aquaporin 4; D006146:Guanidines; D018696:Neuroprotective Agents; D012333:RNA, Messenger; C004479:pimagedine