RESUMEN
Objective To observe the effect of retrograde sinus coronary perfusion on the function of myocardial cell membrane following retrograde sinus coronary perfusion Methods Thirty two isolated rabbit hearts were randomized into 4 groups: Group A, hearts were kept beating by retrograde perfusion with normothermic oxygenated blood; Group B, hearts received retrograde coronary sinus perfusion with warm blood cardioplegia; Group C, hearts received retrograde coronary sinus perfusion with cold blood cardioplegia; Group D, hearts received retrograde coronary sinus perfusion with cold crystalloid cardioplegia After 60 min retrograde perfusion, the hearts were switched on Langendorff Neely antegrade perfused working heart model for other 60 min Free calcium in myocardial cell, myocardial membrane MDA, ATPase and myocardial cell membrane fluidity were measured Results After retrograde coronary sinus perfusion, activity of ATPase and fluidity of the myocardial cell membrane in group A were higher than those in groups B, C and D The contents of myocardial cell membrane MDA and calcium in myocardial cell following retrograde perfusion were much lower in group A than those in groups B and C There was no remarkable difference between group C and group D Conclusion Retrograde perfusion of beating heart is superior to those perfused with warm blood cardioplegia in reducing free radical production, ameliorating paradoxical calcium accumulation in myocardial cell and maintaining activity of ATPase and fluidity of the myocardial cell membrane Warm blood cardioplegia is superior to cold blood cardioplegia