Role of adenosine in local metabolic coronary vasodilation.

摘要: Adenosine has been postulated to mediate the increase in coronary blood flow when myocardial oxygen consumption is increased. The aim of this study was evaluate role adenosine augmented by cardiac paired-pulse stimulation without use catecholamines. In 10 anesthetized closed-chest dogs, measured left circumflex artery, and calculated using arteriovenous difference. Cardiac interstitial concentration estimated from venous arterial plasma measurements a previously described multicompartmental, axially distributed mathematical model. Paired increased heart rate 55 120 beats/min, 104%, 92%, but remained below threshold for vasodilation. After adenosine-receptor blockade with 8-phenyltheophylline (8-PT), were not significantly different control values. Paired-pulse pacing during resulted increases similar response before 8-PT. Coronary did overcome These results demonstrate that required local metabolic pacing-induced consumption.