Delayed neuroprotective effect of sevoflurane on the expression of NF-kappaB following transient focal ischemia-reperfusion in rats

Abstract

To explore the delayed neuroprotective effect of sevoflurane on the expression of NF-kappaB in rat models of transient focal ischemia-reperfusion. Adult male Sprague-Dawley rats (220 approximately 300 g) were randomly assigned into 3 groups:an ischemia-reperfusion (I/R) group, and a 2.5% Sevoflurane (Sevo1) group, and a 4.0% sevoflurane (Sevo2) group. All the rats were subjected to right middle cerebral artery occlusion (MCAO) for 2 hours. The rats in the I/R group were exposed to pure oxygen 60 min at 24 h before MCAO. Sevoflurane preconditioning was induced 24 h before brain ischemia by exposing the rats to 2.5% or 4.0% sevoflurane + oxygen for 60 min. The effects of sevoflurane on the brain was analyzed by evaluating the infarct volume and the expression of NF-kappaB protein through 2, 3, 5-triphenyltetrazolium chloride (TTC) staining and immunohistochemistry at 24 and 72 h after the reperfusion. The infarct volumes were significantly reduced in the Sevo1 and Sevo2 groups at 24 and 72 h after the reperfusion, compared with the I/R group. The expression of NF-kappaB in the ischemic territory increased after cerebral ischemia, sevoflurane could remarkably decrease the expression of NF-kappaB in 24 and 72 h after the reperfusion. Sevoflurane inhibits the expression of NF-kappaB protein during focal ischemia the reperfusion,which may be part of the mechanism of its delayed neuroprotective function.