左卡尼汀强化St.Thomas No.2液对低温离体心脏的保存效果

背景：在心脏瓣膜置换中应用添加左卡尼汀的心脏停搏液可明显减轻心肌线粒体的脂质过氧化反应,保护心肌细胞。目的：观察加入左卡尼汀的St.Thomas No.2液对大鼠离体心脏低温保存的效果。方法：利用Langendorff灌注装置建立SD大鼠离体心脏灌注和工作模型,随机分成4组,其中2组采用St.Thomas No.2液作为心脏停搏液与保存液分别保存心脏4h、6h,另2组采用添加左卡尼汀的St.Thomas No.2液作为心脏停搏液与保存液分别保存心脏4h、6h。结果与结论：与St.Thomas No.2液保存4h组比较,添加左卡尼汀的St.Thomas No.2液保存4h组心脏心率、冠状动脉流量、左心室收缩峰压和左心室内最大上升速率及心肌含水量、ATP含量差别无显著性意义（P〉0.05）,但心肌酶漏出量明显减少（P〈0.05）;添加左卡尼汀的St.Thomas No.2液保存6h组上述指标检测结果均优于St.Thomas No.2保存6h组（P〈0.05）。提示左卡尼汀强化的St.ThomasNo.2液可显著提高大鼠离体心脏的低温保存效果。

Protective effects of St. Thomas No.2 solution supplemented with levocarnitine on preservation of hypothermic heart ex vivo

BACKGROUND：On-pump beating-heart technique has been promoted as better systemic protection compared with the technique of cardioplegic arrest, and the attenuated inflammatory reaction may play an important role in the protective effect of the on-pump beating-heart technique. OBJECTIVE：To observe the protective effects of St. Thomas No.2 solution supplemented with levocarnitine on preservation of hypothermic rat hearts ex vivo. METHODS：Isolated rat heart Langendorff model and working model were established. Thirty-two Sprague-Dawley rats were randomized to four groups with eight rats in each group. In two groups, the hearts were arrested with St.Thomas No.2 solution and preserved in the same solution for 4 hours or 6 hours, while in the other two groups, the hearts were arrested with St.Thomas No.2 solution supplemented with levocarnitine （12 g/L） and preserved in the same solution for 4 hours or 6 hours. RESULTS AND CONCLUSION：Compared with St. Thomas No.2 solution group, after the hearts were preserved for 4 hours, there were no differences in heart rate, coronary artery flow, left ventricular systolic pressure peak, ＋dp/dt max, water content in myocardium, and adenosine triphosphate （P 0.05）, but creatine kinase release was significantly reduced （P 0.05） in the St.Thomas No.2 solution supplemented with levocarnitine group. After the hearts were preserved for 6 hours, the measurement results above-mentioned were superior in the St.Thomas No.2 solution supplemented with levocarnitine group than in the St.Thomas No.2 solution group （P 0.05）. These results suggest that St.Thomas No.2 solution supplemented with levocarnitine provides better effects on preservation of hypothermic rat hearts ex vivo.