title: Effect of melatonin on cerebral edema in rats.
abstract: OBJECTIVE
  Melatonin (5-methoxy-N-acetyltrypamine), a chemical naturally produced in the pineal gland, has been suggested to be a free radical scavenger and an antioxidant. In the present study, the effect of melatonin on cold-induced brain edema was evaluated by determination of cerebral water content, blood-brain barrier permeability, and areas of infarct; the effects were also studied histopathologically.
  
  
  METHODS
  Brain edema was produced in rats by creating a lesion via cortical freezing. Animals were separated into four groups: sham-operated (craniectomy only); control (cold injury); sham-vehicle (cold injury plus saline); and melatonin treatment (cold injury plus melatonin). Melatonin was administered (50 mg/kg intraperitoneally) 15 minutes after the cold injury was induced. Twenty-four hours later, tissue samples from the core, from the periphery of the cold-injured hemisphere, and from the contralateral hemisphere symmetrical to the cold injury were obtained.
  
  
  RESULTS
  Melatonin treatment reduced edema (mean +/- standard deviation; 86.22 +/- 1.54% in the control group versus 80.78 +/- 2.76% in the melatonin treatment group, P < 0.001) and blood-brain barrier permeability (45.34 +/- 2.75% in the control group versus 38.26 +/- 3.40% in the melatonin treatment group, P < 0.001) at the periphery of cold injury. Area of infarct reduced from 5.84 +/- 0.58% in the control group to 3.30 +/- 0.89% in the melatonin treatment group (P < 0.001). The effect of melatonin was also confirmed histopathologically.
  
  
  CONCLUSIONS
  Melatonin was found to be neuroprotective in instances of cold-induced brain edema. Thus, melatonin may be a valuable therapeutic agent in the treatment of cerebral edema.
authors.affiliation: Department of Neurosurgery, School of Medicine, University of Trakya, Edirne, Turkey. askingorgulu@hotmail.com
authors.forename: A
authors.initials: A
authors.lastname: Görgülü
authors.forename: S
authors.initials: S
authors.lastname: Palaoğlu
authors.lastname: Ismailoğlu O
authors.forename: M
authors.initials: M
authors.lastname: Tuncel
authors.forename: M T
authors.initials: MT
authors.lastname: Sürücü
authors.forename: M
authors.initials: M
authors.lastname: Erbil
authors.forename: K
authors.initials: K
authors.lastname: Kilinç
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001812:Blood-Brain Barrier / Q000187:drug effects; D001929:Brain Edema / Q000473:pathology*; D002540:Cerebral Cortex / Q000473:pathology; D016166:Free Radical Scavengers / Q000494:pharmacology*; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D008854:Microscopy, Electron; D051381:Rats; D014882:Water-Electrolyte Balance / Q000187:drug effects
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D008550:Melatonin