Comparison between preconditioning with temporary middle cerebral artery occlusion and 3-Nitropropionic Acid on reduction of brain injuries in rat stroke model

Recent studies suggest that sub-lethal ischemia protects the brain against subsequent ischemic injury. In this study, the nature of changes in the blood brain barrier permeability and brain edema following transient middle cerebral artery ischemia and 3-nitropropionic acid was evaluated. This clinical trial was carried out in Islamic Azad University of Zanjan in summer 2010. Rats were divided into 6 main experimental groups, each containing 28 animals. The first group (model of ischemic preconditioning) was subjected to 10 minutes of transient middle cerebral artery occlusion in the first day and was subjected to 60 minutes of middle cerebral artery occlusion in the second day. The second group (controls) did not receive any intervention except a 60-minute middle cerebral artery occlusion in the second day. The third group (sham) was only subjected to 10 minutes of transient middle cerebral artery occlusion in the first day. The fourth group (intact) was not subjected to any intervention. The fifth group (model of 3-nitropropionic acid preconditioning) received a single dose of 20mg/kg 3-nitropropionic acid in the first day and was subjected to 60 minutes of middle cerebral artery occlusion. The sixth group (control) received normal saline in the first day and a 60-minute middle cerebral artery occlusion in the second day. In the third day, the infarct volume, blood brain barrier permeability and brain edema was evaluated in the groups. Data was analyzed by SPSS 12 software by LSD method. Preconditioning with transient ischemia and 3-nitropropionic acid decreased neurologic deficit scores, infarct volume, brain barrier permeability and brain edema. Transient ischemia and 3-nitropropionic acid are associated with decrease in neurologic deficit scores, infarct volume, blood brain barrier’s permeability and brain edema; therefore, play active role in ischemic protection.