Limb ischemic preconditioning induces brain ischemic tolerance via p38 MAPK

Brain Res. 2006 Apr 21;1084(1):165-74. doi: 10.1016/j.brainres.2006.02.041. Epub 2006 Apr 21.

Abstract

It has been reported that limb ischemic preconditioning (LIP) could induce brain ischemic tolerance. In the present study, we investigated the role of p38 MAPK in the induction of brain ischemic tolerance by observing expression of phosphorylated p38 (p-p38) MAPK in the hippocampus after LIP and the effect of p38 MAPK inhibitor SB 203580 on the protection of LIP against delayed neuronal death (DND) in the CA1 hippocampus induced normally by brain ischemic insult. The results of Flow cytometry and Western blotting showed that expression of p-p38 MAPK initially increased at 6 h after LIP compared with sham group in the CA1 hippocampus. The increases reached peak at 12 h and lasted to 24 h after LIP. Expression of p-p38 MAPK was also increased in the CA3/dentate gyrus (DG) regions after LIP, but the beginning and peaking times were 1 and 3 days after LIP, which were relatively later than those in the CA1. Histological evaluation showed that LIP protected the CA1 hippocampal pyramidal neurons against DND induced by global brain ischemic insult for 8 min, suggesting the occurrence of brain ischemic tolerance. Pretreatment with SB 203580 at 30 min before LIP effectively blocked the ischemic tolerance induced by LIP. Together, it could be concluded that activation of p38 MAPK played an important role in the brain ischemic tolerance induced by LIP, and that components of the p38 MAPK cascade might be targets to modify neuronal survival in ischemic tolerance.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Blotting, Western / methods
  • Brain Ischemia / enzymology*
  • Brain Ischemia / physiopathology*
  • Cell Death / drug effects
  • Cell Death / physiology
  • Enzyme Inhibitors / pharmacology
  • Extremities*
  • Flow Cytometry / methods
  • Gene Expression Regulation / drug effects
  • Imidazoles / pharmacology
  • Ischemic Preconditioning / methods*
  • Male
  • Pyridines / pharmacology
  • Random Allocation
  • Rats
  • Rats, Wistar
  • Time Factors
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • Enzyme Inhibitors
  • Imidazoles
  • Pyridines
  • p38 Mitogen-Activated Protein Kinases
  • SB 203580