Abstract:

Abstract:Objective
To investigate the effects of isoflurane(ISO) preconditioning on the expressions of TNF-α and iNOS mRNA in ischemia reperfusion myocardium of  young rabbits and clarify their mechanisms.Methods 36 young rabbits were randomly divided into three groups,the rabbits in sham operation group were not occluded coronary artery;the rabbits in ischemia-reperfusion (I/R) group were occluded for 30 min and reperfused for 2 h;the rabbits in ISO  preconditioning group were inhaled 1.1% isoflurane for 30 min before ischemia,others were the same to  I/R  group after 15 min.The content of myocardial TNF-α and the expression of iNOS mRNA in myocardioum were determined 30 min after coronary occlusion and 2 h after reperfusion. Results Compared with sham operation group,the contents of myocardial TNF-α in I/R and ISO groups were significantly increased(P<0.05);the content of myocardial TNF-α in ISO group was significantly lower than that in I/R group(P<0.05).The expressions of iNOS mRNA in I/R and ISO groups were significantly higher than that in sham operation group(P<0.05),the expression of iNOS mRNA in ISO group was significantly lower than that in I/R group(P<0.05).Conclusion ISO could reduce the TNF-α content and the expression of iNOS mRNA during I/R injury,which may be one of molecular mechanisms of  ISO  preconditioning in myocardial protection.

Key words: ;ischemia-reperfusion;tumor nectosis factor α;induced nitric oxide synthase