title: A comparative study on the efficacy of 10% hypertonic saline and equal volume of 20% mannitol in the treatment of experimentally induced cerebral edema in adult rats.
abstract: BACKGROUND
  Hypertonic saline and mannitol are commonly used in the treatment of cerebral edema and elevated intracranial pressure (ICP) at present. In this connection, 10% hypertonic saline (HS) alleviates cerebral edema more effectively than the equal volume of 20% mannitol. However, the exact underlying mechanism for this remains obscure. This study aimed to explore the possible mechanism whereby 10% hypertonic saline can ameliorate cerebral edema more effectively than mannitol.
  
  
  RESULTS
  Adult male Sprague-Dawley (SD) rats were subjected to permanent right-sided middle cerebral artery occlusion (MCAO) and treated with a continuous intravenous infusion of 10% HS, 20% mannitol or D-[1-3H(N)]-mannitol. Brain water content (BWC) as analyzed by wet-to-dry ratios in the ischemic hemisphere of SD rats decreased more significantly after 10% HS treatment compared with 20% mannitol. Concentration of serum Na+ and plasma crystal osmotic pressure of the 10% HS group at 2, 6, 12 and 18 h following permanent MCAO increased significantly when compared with 20% mannitol treated group. Moreover, there was negative correlation between the BWC of the ipsilateral ischemic hemisphere and concentration of serum Na+, plasma crystal osmotic pressure and difference value of concentration of serum Na+ and concentration of brain Na+ in ipsilateral ischemic hemisphere in the 10% HS group at the various time points after MCAO. A remarkable finding was the progressive accumulation of mannitol in the ischemic brain tissue.
  
  
  CONCLUSIONS
  We conclude that 10% HS is more effective in alleviating cerebral edema than the equal volume of 20% mannitol. This is because 10% HS contributes to establish a higher osmotic gradient across BBB and, furthermore, the progressive accumulation of mannitol in the ischemic brain tissue counteracts its therapeutic efficacy on cerebral edema.
authors.affiliation: Department of Emergency & Critical Care Medicine, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, PR China. zenghongke@vip.163.com
authors.forename: Hong-Ke
authors.initials: HK
authors.lastname: Zeng
authors.forename: Qiao-Sheng
authors.initials: QS
authors.lastname: Wang
authors.forename: Yi-Yu
authors.initials: YY
authors.lastname: Deng
authors.forename: Wen-Qiang
authors.initials: WQ
authors.lastname: Jiang
authors.forename: Ming
authors.initials: M
authors.lastname: Fang
authors.forename: Chun-Bo
authors.initials: CB
authors.lastname: Chen
authors.forename: Xin
authors.initials: X
authors.lastname: Jiang
mesh_terms: D000818:Animals; D001929:Brain Edema / Q000188:drug therapy* / Q000209:etiology; D004195:Disease Models, Animal; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000188:drug therapy; D008297:Male; D008353:Mannitol / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D009997:Osmotic Pressure / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012462:Saline Solution, Hypertonic / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D012462:Saline Solution, Hypertonic; D008353:Mannitol