Duncker D J, Stubenitsky R, Verdouw P D
Experimental Cardiology, Thoraxcenter, Cardiovascular Research Institute COEUR, Erasmus University Rotterdam, 3000 DR Rotterdam, The Netherlands.
Am J Physiol. 1998 Nov;275(5):H1663-72. doi: 10.1152/ajpheart.1998.275.5.H1663.
A pivotal role for adenosine in the regulation of coronary blood flow is still controversial. Consequently, we investigated its role in the regulation of coronary vasomotor tone in swine at rest and during graded treadmill exercise. During exercise, myocardial O2 consumption increased from 167 +/- 18 micromol/min at rest to 399 +/- 27 micromol/min at 5 km/h (P </= 0.05), which was paralleled by an increase in O2 delivery, so that myocardial O2 extraction (76 +/- 1 and 78 +/- 1% at rest and 5 km/h, respectively) and coronary venous PO2 (24.5 +/- 1.0 and 22.8 +/- 0.3 mmHg at rest and 5 km/h, respectively) remained unchanged. After adenosine receptor blockade with 8-phenyltheophylline (5 mg/kg iv), the relation between myocardial O2 consumption and coronary vascular resistance was shifted toward higher resistance, whereas myocardial O2 extraction rose to 81 +/- 1 and 83 +/- 1% at rest and 5 km/h and coronary venous PO2 fell to 19.2 +/- 0.8 and 18.9 +/- 0.8 mmHg at rest and 5 km/h, respectively (all P </= 0.05). Thus, although adenosine is not mandatory for the exercise-induced coronary vasodilation, it exerts a vasodilator influence on the coronary resistance vessels in swine at rest and during exercise.
腺苷在冠状动脉血流调节中起关键作用这一观点仍存在争议。因此，我们研究了其在静息和分级跑步机运动状态下猪冠状动脉血管张力调节中的作用。运动期间，心肌耗氧量从静息时的167±18微摩尔/分钟增加到5公里/小时时的399±27微摩尔/分钟（P≤0.05），同时氧输送增加，使得心肌氧摄取（静息和5公里/小时时分别为76±1%和78±1%）和冠状静脉血氧分压（静息和5公里/小时时分别为24.5±1.0毫米汞柱和22.8±0.3毫米汞柱）保持不变。在用8-苯基茶碱（5毫克/千克静脉注射）阻断腺苷受体后，心肌耗氧量与冠状动脉血管阻力之间的关系向更高阻力方向转变，而心肌氧摄取在静息和5公里/小时时分别升至81±1%和83±1%，冠状静脉血氧分压在静息和5公里/小时时分别降至19.2±0.8毫米汞柱和18.9±0.8毫米汞柱（所有P≤0.05）。因此，虽然腺苷对于运动诱导的冠状动脉扩张并非必需，但它在静息和运动状态下对猪的冠状动脉阻力血管发挥血管舒张作用。
