Bernauer W
Department of Pharmacology, University of Freiburg, Germany.
Pharmacology. 1996 Nov;53(5):311-9. doi: 10.1159/000139444.
In isolated perfused rat hearts with coronary occlusion and reperfusion, the effect of adenosine antagonists on the release of adenosine and its degradation products inosine, hypoxanthine, xanthine and uric acid was investigated. An antagonist with high selectivity for the A1 receptor, 8-phenyltheophylline, was applied and compared with the relatively unspecific antagonist theophylline, used in its water-soluble form aminophylline. Depending on the duration of coronary occlusion, more or less severe tachyarrhythmias occurred during the myocardial ischemia, and particularly during the subsequent coronary reperfusion. Large amounts of the nucleosides and oxypurines were released after reopening the coronary artery. The release was particularly, high in hearts with ventricular fibrillation. Both adenosine antagonists increased the release in a highly significant way. The findings let assume that adenosine has perhaps a modulating effect on its own release, which can be blocked by adenosine antagonists.
在冠状动脉闭塞和再灌注的离体灌注大鼠心脏中，研究了腺苷拮抗剂对腺苷及其降解产物肌苷、次黄嘌呤、黄嘌呤和尿酸释放的影响。应用了对A1受体具有高选择性的拮抗剂8-苯基茶碱，并与相对非特异性的拮抗剂茶碱（以其水溶性形式氨茶碱使用）进行比较。根据冠状动脉闭塞的持续时间，在心肌缺血期间，尤其是在随后的冠状动脉再灌注期间，会发生或多或少严重的快速性心律失常。重新开放冠状动脉后，大量的核苷和氧嘌呤被释放。在发生心室颤动的心脏中，释放量特别高。两种腺苷拮抗剂都以高度显著的方式增加了释放量。这些发现表明，腺苷可能对其自身的释放具有调节作用，而这种作用可被腺苷拮抗剂阻断。
