单剂晶体停搏液对未成熟心肌能量代谢和超微结构的保护

Effects of single-dose crystalloid cardioplegia on energy metabolism and ultrastructure of immature myocardium

目的:研究低温、多剂和单剂晶体停搏液对未成熟心肌能量代谢和超微结构的保护.方法:建立未成熟幼兔离体工作心模型,利用高效液相色谱法(HPLC)和分光光度法检测未成熟心肌缺血前后心肌高能磷酸化合物(ATP、ADP、AMP 和 CP)和糖原含量,并观察心肌超微结构的改变。结果:缺血再灌注后,Ⅱ组(多剂晶体停搏液组)ATP、CP 和糖原保存最差,分别是4.0±0.4,5.8±0.4μmol/g 干重和639±40/μg/g 干重,Ⅰ组(低温组)和Ⅲ组(单剂灌注组)则相应分别是6.1±0.3,8.8±0.5μmol/g 干重,732±37μg/g 干重(P 均<0.01)和6.0±0.4,9.0±0.5μmol/g 干重,776±50(μg/g 干重(P 均<0.01);心肌超微结构观察显示,Ⅲ组保存优于Ⅰ组和Ⅱ组。结论:单剂晶体停搏液对未成熟心肌能量代谢和超微结构保护最佳。

Objective:This study compared the effects of hypothermia,multiple-dose and single-dose crystalloid cardioplegia on energy matabolism and ultrastructurc of immature myocardium.Methods:The isolated premature rabbit heart model was set up,High-performance liquid chromatography (HPLC) and spectrophotometry were used to measure myocardial high-energy phosphale (ATP、ADP、AMP and CP) and glycogen,whilc myocardial ultrastructures were ob- served after reperfusion.Results:After reperfusion,ATP,CP and glycogen were lowest in group Ⅰ(multiple-dose) 4.0±0.4,5.8±0.4(μmol/g.dry wt)and 639±40(μg/g.dry wt),but were significanly incrcased in group Ⅰ(hy- pothermia)6.1±0.3,8.8±0.5(μmol/g,dry wt),732±37(μg/g,dry wt),(P both<0.01)and in group Ⅱ(single- dose)6.04±0.4,9.0±0.5(μmol/g.dry wt),776±50(μg/g,dry wt)(P<0.01)respectively;group Ⅱ was better than group Ⅰ and group Ⅱ in the pretection of myocardial ultrastructures.Conclusions:The single-dose method of adminis- tering erystalloid cardioplegia provided the best cardioprotection on metabolism and ultrastructures of immature my- ocardium.