不同逆灌方法对兔离体心脏心肌细胞膜脂流动性及膜功能的影响

目的　本实验探讨兔离体心脏经冠状静脉窦不同逆灌方法对心肌细胞膜脂流动性及膜功能的影响。方法　健康成年家兔 3 2只 ,体质量 3 0～ 3 5kg ,随机分为 4组 :A组 (常温氧合血逆灌心脏不停跳 ) ,B组 (温血心脏麻痹液持续逆灌 ) ,C组 (冷血心脏麻痹液持续逆灌 ) ,D组 (冷晶体麻痹液持续逆灌 )。兔离体心脏顺灌左心做功 2 0min ,持续逆灌 60min ,左心做功 60min。比较各组心肌细胞膜脂流动性、心肌细胞膜丙二醛 (MDA)含量、心肌细胞膜ATP酶活性、心肌细胞内钙离子浓度的变化。结果　逆灌后恢复顺灌左心做功第 60分钟B、C、D 3组心肌细胞膜ATP酶活性和心肌细胞膜脂流动性均明显低于A组 (P <0 0 5 ) ,心肌细胞膜MDA含量和心肌细胞内钙离子浓度较A组高 (P <0 0 1)。B组心肌细胞膜ATP酶活性和心肌细胞膜脂流动性优于C、D组 (P <0 0 1) ,B组心肌细胞膜MDA含量和心肌细胞内钙离子浓度明显较C、D组高 (P <0 0 1) ,C、D两组间差异不明显。结论　常温氧合血逆灌心脏不停跳在减轻心肌细胞膜自由基损伤 ,维持膜脂流动性和膜ATP酶功能 ,减轻细胞内钙超载方面优于心脏麻痹液逆灌停搏 ,温血逆灌优于冷血和冷晶体液。

Function of myocardial cellular membrane after retrograde sinus coronary perfusion in isolated rabbit hearts

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