Casiglia E, Paleari C D, Petucco S, Bongiovì S, Colangeli G, Baccilieri M S, Pavan L, Pernice M, Pessina A C
Institute of Clinical Medicine, University of Padova, Italy.
J Hum Hypertens. 1992 Apr;6(2):95-9.
In order to evaluate the effects of 'espresso' Italian coffee on resting flow, blood pressure, and peripheral resistance, 15 non-coffee drinking healthy volunteers received 2 cups of regular coffee, 200 mg purified caffeine or placebo in a latin square double-blind crossover protocol. Before and 30, 60, 90 and 120 min after ingestion, segmental resting flow and BP were measured and peripheral resistance was calculated. An echocardiogram was also performed before and 60 and 120 min after caffeine intake. Both regular coffee and caffeine produced a significant decrease in resting flow and a significant increase in resistance; both systolic and diastolic BP also increased, although not significantly. No variation was observed in heart rate and in cardiac contractility. Placebo (highly decaffeinated coffee for regular coffee and china bitter extract for caffeine) did not produce any haemodynamic effect. In five other healthy volunteers used to drinking more than 5 cups of coffee a day, coffee administration had no effect. These data demonstrate that the caffeine contained in espresso Italian coffee is a vasoconstrictor agent whose effects however are completely blunted in usual coffee drinkers as a consequence of adaptation.
为了评估意式浓缩咖啡对静息血流、血压和外周阻力的影响，15名不喝咖啡的健康志愿者按照拉丁方双盲交叉试验方案，分别饮用了2杯普通咖啡、200毫克纯咖啡因或安慰剂。在摄入前以及摄入后30、60、90和120分钟，测量节段性静息血流和血压，并计算外周阻力。在摄入咖啡因前以及摄入后60和120分钟还进行了超声心动图检查。普通咖啡和咖啡因均使静息血流显著降低，外周阻力显著增加；收缩压和舒张压也有所升高，不过未达显著水平。心率和心脏收缩力未观察到变化。安慰剂（普通咖啡用高度脱咖啡因咖啡，咖啡因用中国苦味提取物）未产生任何血流动力学效应。在另外5名每天饮用超过5杯咖啡的健康志愿者中，饮用咖啡未产生任何影响。这些数据表明，意式浓缩咖啡中所含的咖啡因是一种血管收缩剂，然而由于适应性，其作用在经常喝咖啡的人身上会完全减弱。
