Control of Coronary Blood Flow During Exercise

Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7920, USA.
Exercise and sport sciences reviews (Impact Factor: 4.26). 08/2011; 40(1):37-42. DOI: 10.1097/JES.0b013e3182348cdd
Source: PubMed


GORMAN, M. W. and E.O. FEIGL. Control of coronary blood flow during exercise. Exerc. Sport Sci. Rev., Vol. 40, No. 1, pp. 37-42, 2012. During exercise, coronary blood flow increases to match the augmented myocardial oxygen demand because of tachycardia. Coronary vasodilation during exercise is via a combination of feedforward and feedback control mechanisms. Feedforward control is mediated by sympathetic beta-adrenoceptor vasodilation. Feedback vasodilator control is via a novel hypothesis where adenine nucleotides released from red blood cells act on endothelial purinergic receptors.

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    • "The pivotal role of coronary and muscle blood flow in exercise tolerance in humans is well documented. However, the mechanisms controlling coronary and skeletal muscle blood flow during exercise involving NO, prostacyclin and ATP are not fully understood, but there is a growing body of evidence that multiple endothelial-dependent vasodilator mechanisms compensating each other are involved with erythrocyte-released ATP playing a prominent role in exercise-induced hyperaemia [49] [54] [58] [79] [117]. It is now also clear that moderate-intensity physical training affords vasoprotective, cardioprotective and neuroprotective effects involving endothelium-dependent mechanisms [136] [142] [143] that could be hindered in patients with impaired endothelial function. "
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