Tanaka T, Fukumoto T, Ochi T, Kuroiwa A
Division of Clinical Physiology, School of Nursing and Medical Technology, University of Occupational and Environmental Health, Japan.
Int J Cardiol. 1990 Dec;29(3):373-80. doi: 10.1016/0167-5273(90)90128-r.
To study the role of endogenous adenosine in coronary dilatation induced by beta-adrenergic stimulation, isolated rat hearts were perfused at a constant flow rate. Perfusion of the heart with isoproterenol caused increases in the heart rate, left ventricular developed pressure, coronary dilatation, and release of adenosine and its degradation products. Theophylline inhibited isoproterenol-induced coronary dilatation without any significant effects on other contractile properties such as heart rate and left ventricular developed pressure. Coronary dilatation induced by exogenous adenosine was also inhibited by theophylline. These results suggest that beta-adrenergic stimulation induces coronary vasodilatation not only through direct beta-adrenergic responses, but also through increases in extracellular adenosine.
为研究内源性腺苷在β-肾上腺素能刺激诱导的冠状动脉扩张中的作用，以恒定流速灌注离体大鼠心脏。用异丙肾上腺素灌注心脏可导致心率、左心室舒张末压、冠状动脉扩张以及腺苷及其降解产物的释放增加。茶碱抑制异丙肾上腺素诱导的冠状动脉扩张，而对心率和左心室舒张末压等其他收缩特性无显著影响。茶碱也抑制外源性腺苷诱导的冠状动脉扩张。这些结果表明，β-肾上腺素能刺激不仅通过直接的β-肾上腺素能反应，还通过细胞外腺苷的增加诱导冠状动脉血管舒张。
