RESUMEN
ObjectiveTo investigate the effect of isoflurane preconditioning on calcitonin gene-related peptide (CGRP) and NF-kappa B following local cerebral ischemia/reperfusion (I/R) in rabbits.MethodsFiftyfour adult New Zealand white rabbits of both sexes weighing 2.0-2.5 kg were randomly divided into three groups (n ＝ 18 each):sham operation group (group S),group I/R and isoflurane preconditioning group(group I).After anesthesia induction with intramuscular injection of ketamine 70 mg/kg and scopolamine 0.006 mg/kg and maintenance of anesthesia with intravenous injection of midazolam 0.1 mg/kg,fentanyl 0.01 mg/kg and vecuronium 0.1 mg/kg,endotracheal intubation was performed and mechanical ventilation was employed.In groups I/R and S,midazolam at 0.1 mg·kg-1·h-1 was infused through the left ear vein.After the rabbits in group I inhaling 1.4％ isoflurane for 30 minutes,which was then eluted for 10 minutes,local cerebral ischemia was made in groups I/Rand I with thread ligation method and reperfusion was made 2 hours later,simultaneously midasolam at 0.1 mg·kg- 1 · h - 1 was injected.All the rabbits in three groups were infused with fentanyl at 0.05 mg· kg- 1 · h- 1 and vecurenium at 0.10 mg· kg-1 · h-1.After blood samples were collected from the central artery of the ear for determination of plasma CGRP before anesthesia,immediately before reperfusion,and 1,2,3,4,and 5 h of reperfusion,all the animals were sacrificed at the corresponding time points and brain tissues were obtained for determination of NF-κB activity and its expression with Western blotting and immunohistochemistry staining.ResultsThe plasma concentration of CGRP,the activity and expression of NF-κB were higher in group I/R than in group S ( P <0.05).The plasma concentration of CGRP was higher and the activity and expression of NF-κB were lower in group I than in group I/R ( P < 0.05 ).ConclusionIsoflurane preconditioning can reduce local cerebral I/R injury in rabbits through promoting CGRP release and inhibiting NF-κB function.