B型钠尿肽对心力衰竭生物工程模型肾血流动力学的影响

背景：肾循环灌注减少、肾血流降低会造成肾损伤，心力衰竭患者合并肾损伤会明显增加死亡率。但B型钠尿肽对于心力衰竭患者肾功能的影响目前存在较大争论，关于B型钠尿肽对心力衰竭肾灌注的研究很少。 目的：评价不同剂量重组人B型钠尿肽对急性心肌梗死伴心力衰竭生物工程模型肾循环的血流动力学效应。 方法：应用前降支球囊闭塞结合微血栓悬液灌注构建急性心肌梗死伴心力衰竭约克猪模型共12头，随机分入重组人B型钠尿肽组和对照组（n=6）。重组人B型钠尿肽组给予重组人B型钠尿肽1.5μg/kg，2 min内匀速静推后，以0.010μg/（kg min）静脉泵入60 min，然后依次加量至0.020μg/（kg min）、0.030μg/（kg min）静脉泵入各60 min。对照组依照相同给药方法给予生理盐水。在球囊闭塞前、成模后即刻、不同剂量重组人B型钠尿肽给药后60 min，行肾动脉造影，比较肾动脉管径的变化。多普勒导丝测定肾动脉平均峰值速率。计算平均动脉压和跨肾灌注压。 结果与结论：造模成功后与基线比较，肾动脉管径无变化，肾动脉平均峰值速率明显下降，肾动脉血流量显著降低，肾动脉血管阻力明显升高，跨肾灌注压明显降低。给予重组人B型钠尿肽0.010μg/（kg min）后可见肾动脉扩张，并随剂量增加，肾动脉直径继续增加。肾动脉平均峰值速率增高，但较基线差异无显著性意义，此后，随剂量增加，肾动脉平均峰值速率逐渐下降。给药后肾动脉血管阻力逐渐下降，呈剂量依赖性。跨肾灌注压随着药物剂量的升高进行性下降，至0.030μg/（kg min）泵入时显著低于对照组。给予重组人B型钠尿肽后肾动脉血流量逐渐升高，最高点出现在0.020μg/（kg min）。结果可见急性心肌梗死伴心力衰竭模型应用重组人B型钠尿肽可增加肾灌注，0.020μg/（kg min）效果最强。

Effect of recombinant human B-type natriuretic peptide on renal hemodynamics in a bioengineering model of acute myocardial infarction with heart failure

BACKGROUND：The reduction of renal circulation and perfusion, the decline of renal blood flow, wil al cause renal injury. The heart failure concomitant with renal injury can significantly increase the mortality. But there are arguments about the effect of B-type natriuretic peptide （BNP） on the renal function of patients with heart failure, and little evidence is known about the effect of BNP on the renal hemodynamics. OBJECTIVE：To evaluate the effects of different dosages of recombinant human BNP on renal perfusion in bioengineering models of acute myocardial infarction with heart failure. METHODS：Bioengineering model of York pigs of acute myocardial infarction with heart failure was established with the method of occluding anterior descending branch with bal oon and injecting microthrombus. The models were randomized into recombinant human BNP group and control group （n=6）. Clinical dose of recombinant human BNP （bolus of 1.5μg/kg fol owed by a continuous infusion of 0.01μg/（kg.min） for 60 minutes, and then a＆amp;nbsp;continuous infusion of 0.02 and 0.03μg/（kg.min） for 60 minutes） was administrated in the BNP group, while equal volume of saline was given in the control group. Renal artery diameter, average peak velocity, mean arterial pressure and transrenal perfusion pressure were recorded at baseline, instantly after the model establishment, 60 minutes after continuous infusion of recombinant human BNP. RESULTS AND CONCLUSION：Compared with baseline information, renal artery diameter maintained unchanged after the models were established, average peak velocity was significantly decreased, renal arterial blood flow was significantly reduced, renal vascular resistance was obviously increased, and transrenal perfusion pressure was obviously decreased. After infusion of 0.01μg/（kg.min） recombinant human BNP, renal arteries began to dilute, renal artery diameter was gradual y increased. The average peak velocity was also increased, but showed no significant differences com