Jeserich M, Just H
Medizinische Universitätsklinik, Abteilung III (Schwerpunkt für Kardiologie und Angiologie), Freiburg.
Z Kardiol. 1998 Feb;87(2):77-83. doi: 10.1007/s003920050157.
Nitrates act, in part, by causing systemic venodilation. In addition, nitrates lead to dilation of arterial conductance vessels. The maximal dilation capacity and threshold of arterial conductance vessels have so far not been examined thoroughly. Therefore, we tested the radial artery diameter before and after i.v. nitroglycerin infusions at increasing dosages (0.015, 0.05, 0.15, 0.5, and 1.5 micrograms/kg/min), 7 min each dose in 28 patients with suspected coronary artery disease (mean age +/- SEM 58 +/- 2 years) using a high resolution ultrasound devise. The low doses of 0.05 and 0.15 microgram/kg/min, equal to dose of 2.5 mg/12 hours and 7.5 mg/12 hours in a patient with 70 kg, led to substantial increases in the cross sectional luminal area of the radial artery of 14.8 +/- 1.5% and 29.3 +/- 2.2%*, (*p < 0.05 vs baseline). The maximal increase (dilatory capacity) was 53.8 +/- 3.8% (mean diameter at baseline: 2.7 +/- 0.1 mm, maximal 3.4 +/- 0.1 mm, p < 0.001). The nitrate sensitivity of the radial artery was estimated by calculation of the ED50, the dose that caused half-maximal dilation of the radial artery. The ED50 of the radial artery was 0.13 +/- 0.003 microgram/kg/min. In conclusion, nitroglycerin leads to a dose dependent dilatation of peripheral conductance vessels. Low doses of 0.05 and 0.15 microgram/kg/min lead to significant arterial dilation. The maximal dilatory capacity of the radial artery is 53.8 +/- 3.5%.
硝酸盐部分通过引起全身静脉扩张起作用。此外，硝酸盐会导致动脉传导血管扩张。迄今为止，动脉传导血管的最大扩张能力和阈值尚未得到充分研究。因此，我们使用高分辨率超声设备，对28例疑似冠心病患者（平均年龄±标准误58±2岁）在静脉输注不同剂量（0.015、0.05、0.15、0.5和1.5微克/千克/分钟）的硝酸甘油前后的桡动脉直径进行了测试，每个剂量输注7分钟。低剂量0.05和0.15微克/千克/分钟，相当于体重70千克患者2.5毫克/12小时和7.5毫克/12小时的剂量，导致桡动脉横截面积显著增加，分别为14.8±1.5%和29.3±2.2%*，（*与基线相比，p<0.05）。最大增加量（扩张能力）为53.8±3.8%（基线平均直径：2.7±0.1毫米，最大3.4±0.1毫米，p<0.001）。通过计算引起桡动脉半最大扩张的剂量（ED50）来估计桡动脉对硝酸盐的敏感性。桡动脉的ED50为0.13±0.003微克/千克/分钟。总之，硝酸甘油导致外周传导血管剂量依赖性扩张。0.05和0.15微克/千克/分钟的低剂量导致显著的动脉扩张。桡动脉的最大扩张能力为53.8±3.5%。
