Effect Of Sevoflurane On Reperfusion Injury After Regional Myocardial Ischemia In Immature Rabbits In Vivo

Objective: To investigate the effects of sevoflurane on cytokines TNF- a and IL-6 levels in serum, myocardial apoptosis and Bcl-2 and Bax protein expression in immature rabbits heart in vivo after regional myocardial ischemia-reperfusion (I/R). Methods: Eighteen immature rabbits (one to two weeks old and weighting 290-375g) were randomly divided into three groups ( 6 animals/group) : (Ⅰ) control group (C); (Ⅱ) ischemia-reperfusion group (I/R); (Ⅲ) sevoflurane + ischemia-reperfusion group (S). The animals were anesthetized with intramuscular injection of ketamine (80mg/kg). Chest was opened and heart exposed. Left coronary artery was temporarily occluded for 30 min followed by 120 min reperfusion at lmm inferior to left auricle. Myocardial ischemia was confirmed by decoloration of apex. In group C, heart was exposed but left coronary artery was not occluded. In group I/R, left coronary artery was occluded for 30 min followed by 120 min reperfusion. In group S, sevoflurane was inbreathed during operation, ischemia and reperfusion. The animals were sacrificed at the end of 120 min reperfusion. Blood samples were taken at the beginning of ischemia (To), 30 min of ischemia (T1) and 120 min of reperfusion for determination of serum IL-6 and TNF- α levels (enzyme-linked immunosorbent assay ELISA). Myocardium was obtained for determination of myocardial apoptosis (TUNEL) and Bax and Bcl-2 protein expression (immunohistochemistry technique ).Results: The serum IL-6 level in group S was lower than those in group I/R, but higher than those in group C. The serum TNF- α level was same in three group. The number of apoptosis myocardial cell in group S was less than those in group I/Rbut more than those in group C (p<0.05). Bax protein expression increased significantly in group I/R and group S compared with those in group C, and there was significantly less expression in group S than in group I/R (p<0.05). Bcl-2 protein expression increased significantly in group S than those in group C and group I/R. Conclusion: Sevoflurane can attenuate the increasing of serum IL-6 level, myocardial apoptosis and Bax protein expression, and increase Bcl-2 protein expression during myocardial ischemia-reperfusion in immature rabbit in vivo. Sevoflurane has protection on immature myocardial ischemia-reperfusion.