Manfredi J P, Sparks H V
Am J Physiol. 1982 Oct;243(4):H536-45. doi: 10.1152/ajpheart.1982.243.4.H536.
If adenosine (ADO) mediates metabolic vasodilation in the heart, increases in interstitial ADO (ISF[ADO]) must accompany increases in coronary vascular conductance. We tested this using ADO release, defined as the difference in [ADO] in coronary venous and arterial plasma multiplied by coronary plasma flow, as an index of ISF[ADO]. Pentobarbital-anesthetized dogs received intravenous norepinephrine or left atrial pacing, and the resulting changes in coronary blood flow (delta CBF), conductance (delta C), myocardial oxygen consumption (delta VO2), and ADO release (delta RADO) were measured. If ISF[ADO] and C are coupled, the ratio delta RADO/delta C should be greater than zero. For dogs receiving atrial pacing, the ratios delta RADO/delta C, delta RADO/delta CBF, and delta RADO/delta VO2 equal -2.4 +/- 2.2 nmol . mmHg-1 . ml-1, -0.022 +/- 0.020 nmol/ml, and -0.13 +/- 0.12 nmol/ml, respectively. These values do not differ from zero. For dogs receiving norepinephrine, delta RADO/delta C, delta RADO/delta CBF, and delta RADO/delta VO2 equal 9.7 +/- 1.8, 0.051 +/- 0.017, and 0.44 +/- 0.13, respectively. These values are greater than zero (P less than 0.05). These differences between atrial pacing and norepinephrine infusion rate observed despite similar changes in C, CBF, and VO2. We conclude that ADO may mediate the vasodilation induced by norepinephrine, but not atrial pacing.
如果腺苷（ADO）介导心脏的代谢性血管舒张，那么冠状动脉血管传导性增加时，组织间液中ADO（ISF[ADO]）必然也会增加。我们通过将ADO释放（定义为冠状静脉和动脉血浆中[ADO]的差值乘以冠状血浆流量）作为ISF[ADO]的指标来对此进行测试。用戊巴比妥麻醉的犬接受静脉注射去甲肾上腺素或左心房起搏，并测量由此导致的冠状动脉血流（ΔCBF）、传导性（ΔC）、心肌耗氧量（ΔVO2）和ADO释放（ΔRADO）的变化。如果ISF[ADO]与C相关联，那么ΔRADO/ΔC的比值应大于零。对于接受心房起搏的犬，ΔRADO/ΔC、ΔRADO/ΔCBF和ΔRADO/ΔVO2的比值分别为-2.4±2.2 nmol·mmHg-1·ml-1、-0.022±0.020 nmol/ml和-0.13±0.12 nmol/ml。这些值与零无差异。对于接受去甲肾上腺素的犬，ΔRADO/ΔC、ΔRADO/ΔCBF和ΔRADO/ΔVO2分别为9.7±1.8、0.051±0.017和0.44±0.13。这些值大于零（P<0.05）。尽管C、CBF和VO2有相似的变化，但心房起搏和去甲肾上腺素输注率之间仍存在这些差异。我们得出结论，ADO可能介导去甲肾上腺素诱导的血管舒张，但不介导心房起搏诱导的血管舒张。
