Delayed neuroprotection induced by sevoflurane via opening mitochondrial ATP-sensitive potassium channels and p38 MAPK phosphorylation

Neurol Sci. 2012 Apr;33(2):239-49. doi: 10.1007/s10072-011-0665-6. Epub 2011 Jul 1.

Abstract

This study aimed to investigate the role of p38 MAPK phosphorylation and opening of the mitoK(ATP) channels in the sevoflurane-induced delayed neuroprotection in the rat brain. Adult male Sprague-Dawley rats (250-300 g) were randomly assigned into four groups: ischemia/reperfusion (Control), sevoflurane (Sevo), 5-hydroxydecanoate (5-HD) + sevoflurane (5-HD + Sevo) and 5-HD groups and were subjected to right middle cerebral artery occlusion (MCAO) for 2 h. Sevoflurane preconditioning was induced 24 h before MCAO in sevoflurane and 5-HD + sevoflurane groups by exposing the animals to 2.4% sevoflurane in oxygen for 60 min. In control and 5-HD groups: animals were exposed to oxygen for 60 min at 24 h before MCAO. A selective mitoK(ATP) channel antagonist, 5-hydroxydecanoate (5-HD, 40 mg/kg, i.p.), was administered 30 min before sevoflurane/oxygen exposure in the 5-HD + sevoflurane and 5-HD groups, respectively. Neurological deficits scores and the protein expression of phosphorylated p38 mitogen-activated protein kinase (p-p38 MAPK) were evaluated at 24 and 72 h after reperfusion. Cerebral infarct size was evaluated at 72 h after reperfusion by 2,3,5-triphenyltetrazolium chloride staining. Sevoflurane preconditioning produced marked improvement neurological functions and a reduction in brain infarct volumes than animals with brain ischemia only. Sevoflurane treatment also caused increased phosphorylation of p38 MAPK at 24 and 72 h after reperfusion. These beneficial effects were attenuated by 5-HD. Blockade of cerebral protection with 5-HD concomitant with decrease in p38 phosphorylation suggests that mitoK(ATP) channels opening and p38 phosphorylation participate signal transduction cascade of sevoflurane preconditioning and p38 MAPK activation may be a downstream of opening mitoK(ATP) channels.

MeSH terms

  • Analysis of Variance
  • Animals
  • Anti-Arrhythmia Agents / pharmacology
  • Brain Infarction / etiology
  • Brain Infarction / prevention & control
  • Cell Count
  • Decanoic Acids / pharmacology
  • Disease Models, Animal
  • Gene Expression Regulation / drug effects
  • Hydroxy Acids / pharmacology
  • Infarction, Middle Cerebral Artery / drug therapy*
  • Ischemic Preconditioning / methods
  • Male
  • Methyl Ethers / therapeutic use*
  • Neuroprotective Agents / therapeutic use*
  • Phosphorylation / drug effects
  • Potassium Channels / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Sevoflurane
  • Time Factors
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • Anti-Arrhythmia Agents
  • Decanoic Acids
  • Hydroxy Acids
  • Methyl Ethers
  • Neuroprotective Agents
  • Potassium Channels
  • mitochondrial K(ATP) channel
  • Sevoflurane
  • 5-hydroxydecanoic acid
  • p38 Mitogen-Activated Protein Kinases