Smulyan H, Mookherjee S, Warner R A
Circulation. 1986 Jun;73(6):1264-9. doi: 10.1161/01.cir.73.6.1264.
Nitroglycerin acts, in part, to reduce arterial impedance, and thus left ventricular work. The reduction in arterial impedance is largely attributable to a fall in systemic vascular resistance, but may also be due to an increased distensibility of the arterial tree. In this study, volume distensibility of forearm arteries was calculated from measurements of pulse-wave velocity before and during intravenous nitroglycerin infusion. Since a fall in blood pressure itself increases arterial distensibility, the induced blood pressure change was controlled as a variable by repeating the measurements with the subject's forearm in a plastic cylinder and repeating the measurements at a variety of altered cylinder pressures. At every studied pressure, nitroglycerin infusion increased forearm arterial distensibility, demonstrating another way in which nitroglycerin reduces left ventricular afterload. Since the pulsatile portion of cardiac work is approximately 10% of total work, the magnitude of this nitroglycerin effect on cardiac function is probably small.
硝酸甘油部分作用是降低动脉阻抗，从而减轻左心室负荷。动脉阻抗的降低很大程度上归因于全身血管阻力的下降，但也可能是由于动脉树的扩张性增加。在本研究中，通过测量静脉输注硝酸甘油前后的脉搏波速度来计算前臂动脉的容积扩张性。由于血压下降本身会增加动脉扩张性，因此通过将受试者的前臂置于塑料圆筒中重复测量，并在不同的圆筒压力下重复测量，将诱导的血压变化作为一个变量进行控制。在每个研究压力下，输注硝酸甘油均增加了前臂动脉扩张性，这表明硝酸甘油降低左心室后负荷的另一种方式。由于心脏做功的脉动部分约占总功的10%，因此硝酸甘油对心脏功能的这种影响程度可能较小。
