停搏液中Ca2+浓度对未成熟心肌的影响

目的 :探讨未成熟心肌停搏液中合适的 Ca2 +浓度。方法 :建立未成熟心肌细胞缺氧 /复氧损伤模型和未成熟离体心脏缺血 /再灌注损伤模型。采用荧光指示剂法测定心肌细胞内游离钙离子浓度和荧光微量法测定细胞内丙二醛 （MDA）含量 ;测定离体心脏心功能变化。结果 :当心脏停搏液中 Ca2 +浓度为 1.2 mm ol/ L 时 ,在常温未成熟心肌细胞缺氧 /复氧损伤中 ,细胞内钙超载、脂质过氧化反应较轻 ;而在离体心脏模型中 ,心功能恢复比与停搏液中 Ca2 +浓度的关系呈顶部较平坦的曲线 ,以 Ca2 +浓度为 1.0 mmol/ L 时恢复较佳。结论 :停搏液中适合未成熟心肌的 Ca2 +浓度为 1.0～ 1.2 m mol/ L。

Effect of calcium content of the cardioplegic solution on immature myocardium

AIM:To study the suitable calcium content of the cardioplegic solution for the immature myocardium.METHODS:Models of cultured myocardial cells of neonatal rats and isolated working immature rat hearts were established. Intracellular free Ca 2+ contents and MDA levels were measured by mean of fluorescence indicators and function of isolated working immature rat hearts were tested. RESULTS:In 1.2 mmol/L Ca 2+ cardioplegic solution,only slight reaction of liqid peroxidation occurred and calcium was overloaded in hypoxia and reoxygenation injuries of immature myocardial cells;a bell-shaped,dose-response profole for calcium with optimal protection occurred at 1.0 mmol/L during function recovery of immature rat hearts.CONCLUSION:The optimal calcium concentration of cardioplegic solution is 1.0 mmol/L to 1.2 mmol/L for the immature myocardium.