Mechanism of hyperbaric oxygen preconditioning in neonatal hypoxia-ischemia rat model

Brain Res. 2008 Feb 27;1196:151-6. doi: 10.1016/j.brainres.2007.12.039. Epub 2007 Dec 28.

Abstract

Hypoxic ischemic (HI) injury in neonates damages brain tissues. We examined the mechanism of hyperbaric oxygen preconditioning (HBO-PC) in neonatal HI rat model. Seven-day-old rat pups were subjected to left common carotid artery ligation and hypoxia (8% oxygen at 37 degrees C) for 90 min. HBO (100% O(2), 2.5 atmospheres absolute for 2.5 h) were administered by placing pups in a chamber 24 h before HI insult. Brain injury was assessed by the survival rate, 2,3,5-triphenyltetrazolium chloride (TTC), Nissl, TUNEL straining and caspase-3,caspase-9 activities after HI. In HBO preconditioned animals, survival rate was increased, infarct ratio was decreased, and the positive stained TUNEL cells were reduced, accompanied by the suppression of caspase-3 and -9 activities. These results indicate that a single HBO-PC appears to provide brain protection against HI insult via inhibition of neuronal apoptosis pathways.

MeSH terms

  • Analysis of Variance
  • Animals
  • Animals, Newborn
  • Brain Infarction / etiology
  • Brain Infarction / prevention & control
  • Caspase 3 / metabolism
  • Caspase 9 / metabolism
  • Cell Count
  • Cell Death
  • Disease Models, Animal
  • Hyperbaric Oxygenation*
  • Hypoxia-Ischemia, Brain / pathology
  • Hypoxia-Ischemia, Brain / prevention & control*
  • Hypoxia-Ischemia, Brain / therapy*
  • In Situ Nick-End Labeling / methods
  • Ischemic Preconditioning / methods*
  • Rats
  • Rats, Sprague-Dawley
  • Tetrazolium Salts

Substances

  • Tetrazolium Salts
  • triphenyltetrazolium
  • Caspase 3
  • Caspase 9