Hopkins B E, Taylor R R
J Clin Invest. 1974 Jun;53(6):1716-25. doi: 10.1172/JCI107723.
The hemodynamic and phasic ascending aortic flow changes induced by acetylstrophanthidin and glucagon were studied in closed-chest sedated dogs with aortic regurgitation. While the positive inotropic effect of both agents was reflected in an increase in peak rate of rise of left ventricular pressure, acetylstrophanthidin increased aortic regurgitation, while glucagon decreased it. With the former, left ventricular end-diastolic pressure rose from 20+/-6 to 27+/-6 mm Hg (P < 0.005), but fell from 18+/-4 to 11+/-3 mm Hg (P < 0.001) with glucagon. Acetylstrophanthidin increased systemic vascular resistance, aortic diastolic pressure, and diastolic regurgitant flow rate, and, heart rate and the duration of regurgitation per beat and per minute being unchanged, regurgitant flow per beat increased 32+/-15% (P < 0.001). Glucagon decreased regurgitant flow per beat 27+/-14% (P < 0.001) because of abbreviation of diastole associated with tachycardia, and because of reduction in regurgitant flow rate. Despite tachycardia, the duration of regurgitation per minute was unchanged, and the small fall in regurgitant blood flow per minute was not significant, but this pertained in the face of 47% increase in effective cardiac output (P < 0.001). In contrast, acetylstrophanthidin increased regurgitant flow per minute 28+/-14% (P < 0.001) without change in effective cardiac output. The increase in cardiac contractility, tachycardia, and systemic vasodilatation induced by glucagon preferentially enhanced forward blood flow, which led to reduction in left ventricular volume overload, while it increased cardiac output. Contrarily, acetylstrophanthidin increased aortic regurgitation and, despite its inotropic effect, increased left ventricular volume overload without an increase in cardiac output.
在患有主动脉反流的闭胸镇静犬中，研究了毒毛花苷和胰高血糖素引起的血流动力学和阶段性升主动脉血流变化。虽然两种药物的正性肌力作用都反映在左心室压力上升峰值速率的增加上，但毒毛花苷增加了主动脉反流，而胰高血糖素则降低了主动脉反流。使用前者时，左心室舒张末期压力从20±6毫米汞柱升至27±6毫米汞柱（P<0.005），但使用胰高血糖素时则从18±4毫米汞柱降至11±3毫米汞柱（P<0.001）。毒毛花苷增加了全身血管阻力、主动脉舒张压和舒张期反流流速，且心率以及每搏和每分钟反流持续时间不变，每搏反流流量增加了32±15%（P<0.001）。胰高血糖素使每搏反流流量降低27±14%（P<0.001），这是由于与心动过速相关的舒张期缩短以及反流流速降低。尽管心动过速，但每分钟反流持续时间不变，每分钟反流血流量的小幅下降并不显著，但这是在有效心输出量增加47%的情况下出现的（P<0.001）。相比之下，毒毛花苷使每分钟反流流量增加28±14%（P<0.001），而有效心输出量无变化。胰高血糖素引起的心肌收缩力增强、心动过速和全身血管舒张优先增强了前向血流，这导致左心室容量超负荷减轻，同时增加了心输出量。相反，毒毛花苷增加了主动脉反流，并尽管其具有正性肌力作用，但增加了左心室容量超负荷，而心输出量并未增加。
