Effects of inhalational anesthetic pretreatment on myocardial Bcl 2, Bax and p53 gene expression during ischemia / reperfusion in rabbits / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of pretreatment with different inhalational anesthetic agents on myocardial Bcl-2, Bax and p53 gene expression during ischemia-reperfusion ( I/R) in rabbits. MethodsForty New Zealand white rabbits of both sexes were anesthetized with intramuscular ketamine 70 mg kg-1 tracheotomized and mechanically ventilated with 100% O2. PETCO2 was maintained at 4.0-4.5 kPa. Carotid artery and external jugular vein were cannulated for BP monitoring, fluid administration and medication. Anesthesia was maintained with midazolam 0.05-0.1 mg kg-1?h-1 , ketamine 2-5 mg? kg-1?h-1and vecuronium 0.05-0.1 mg? kg -1 ? h-1 . Myocardial ischemia was induced by occlusion of anterior descending branch of left coronary artery. Ischemia was confirmed by cyanosis of local myocardium and elevation of S-T segment. The animals were randomly allocated to one of five groups with 8 animals in each group group C sham operation; group I/R; group I isoflurane pretreatment; group S sevoflurane pretreatment and group D desflurane pretreatment. In guoup C animals underwent no I/R. In group I/R animals were subjected to 3h of ischemia followed by 3 h reperfusion. In group I, S and D animals inhaled 1.1% isoflurane or 2% sevoflurane or 6% desflurane for 30 min followed by 15 min of wash-out before I/R. Intravenous anesthetic infusion was suspended while inhalational anesthetic was being inhaled. Myocardium 100 mg was obtained from marginal zone of ischemic area and made into cell suspension for determination of apoptosis index ( AI) and expression of Bcl-2, Bax and p53 genes, using flow cytometry.ResultsAI was (14)% in group I/R and was significantly reduced to (6.7 ? 1.8)% ( group Ⅰ ), (6.7 ? 1.6)% ( group S) and (7.4?2.0)% ( group D) (P