The protective effect of dexmedetomidine against focal cerebral ischemia/reperfusion injury in rats and its mechanism / 中华行为医学与脑科学杂志

ABSTRACT

Objective To explore the neuroprotective effect of dexmedetomidine ( Dex) in rats ex-posed to focal cerebral ischemia/reperfusion ( I/R) induced by middle cerebral artery occlusion ( MCAO) and the possible mechansims.Methods Adult male Sprague-Dawley rats were subjected to MCAO for 90 min followed by reperfusion for 24 h and Dex ( 15μg? kg-1 ) was infused through the left femoral vein im-mediately after the onset of MCAO.The PI3K inhibitor LY294002 ( LY,10 mM,10 μl) or eNOS inhibitor L-NIO ( 1 mg? kg-1 ,10μl) was intracerebroventricular administered before ischemia using a microinjecton. The neurological deficit score,brain edema,cerebral infarct volume,and neuron survivals were evaluated after 24 h of reperfusion.The expression of p-Akt ( Ser473) and p-eNOS ( Ser1177) in the ischemic hemicere-brum was detected by Western Blot.Results Compared with I/R group,the neurological deficit score,cere-bral infarct volume,and the degree of brain edema were significantly reduced in the rats treated with Dex ((2.3±0.4) vs (3.9±0.6),(19.3±3.5)%vs (40.5±5.4)%,(61.8±8.1)%vs (76.3±8.5)%,all P0.05).Conclusion Dex can reduce cerebral injury in rats exposed to focal I/R,which is mediated by the activation of PI3K/Akt-eNOS pathway.