三磷酸腺苷-氯化镁对“迟呆”心肌钙离子含量和舒缩功能恢复的影响

Effects of adenosine triphosphate- magnesium chloride on the myo- cardial calcium ion content and the cardiac function of "stunned" iso- lated rat hearts

作者利用离体大鼠工作心脏模型,观察了再灌注时给予三磷酸腺苷-氯化镁(ATP-MgCl_2)9×10^(-4)mmol/L,对20 min停灌/再灌注心脏舒缩功能恢复和心肌Ca^(2+)含量的影响作用.再灌注10 min时,再灌注伊始给药组和单纯再灌组主要心功能指标的恢复率分别为:左室发展压(DP)98.8%±7.5%比76.1%±12.7%,+dp/dt_(max)96.9%±7.8%比79.1%±13.3%,-dp/dt_(max)79.9%±11.0%比61.3%±22.8%,等容舒张期心室内压下降时间常数(T)169.3%±45.6%比216.9%±71.4%,每分主动脉流量(aCO)87.3%±6.1%比43.0%±20.2%.两组心肌Ca^(2+)含量为52.55±8.08μg/g·dry wt和80.64±17.37μg/g·dry wt.统计分析结果均示有显著差异(P<0.05或P<0.01).当再灌注20min给药时,则药物作用效果不明显.结果表明:再灌注伊始给予ATP-MgCl_2能明显减轻心肌“迟呆”的程度,这可能和该药具有减轻心肌再灌注损伤的作用有关。

The isolated working rat hearts were made 20 min ischemia, and during reperfusion the myocardium became 'stunned'. When adenosine triphosphate-magnesium chloride (ATP-MgCl2) 9×10-4 mmol/L was given from the beginning of reperfusion (n=10), the parameters of cardiac function recovered better than those in simple reperfusion group (n=10): at 10 min of reperfusion (% preischemic value), left ventricular developed pressure (DP) 98.8%±7.5% vs 76.1%±12.7% (P<0.01), +dp/dtmat 96.9% ± 7.8% vs 79.1%±133% (P<0.01), -dp /dtmax 79.9%±11.0% vs 61.3%± 22.8% (P<0.05), time constant of isovolumic diastolic pressure decay (T) 169.3%±45.6% vs 216.9%±71.4% (P<0.05), aortic cardiac output (aCO) 873%±6.1% vs 43.0%±20.2% (P<0.01) . The myocardial Ca2+ content was also lower in the ATP-MgCl2 group than in the simple reperfusion group 52.55±8.08 vs 80.64±17.37μg/g·dry wt (P<0.01). These results indicate that ATP-MgCl, used from the beginning of reperfusion can improve recovery of function of stunned myocardium. But the authors couldn't find this effect when ATP-MgCl2 was used at 20 min reperfusion.