Böhm M, Gierschik P, Ungerer M, Erdmann E
Medizinische Klinik I der Universität München, F.R.G.
Eur J Pharmacol. 1989 Oct 17;172(4-5):407-11. doi: 10.1016/0922-4106(89)90022-9.
The adenosine receptors in myocardial membranes of human explanted hearts were labeled with the radiolabeled ligand [3H]DPCPX (1,3-dipropyl-8-cyclopentylxanthine). Agonist competition curves revealed high- and low-affinity states. The addition of guanylyl imidodiphosphate (Gpp (NH)p) converted all receptors to a low-affinity state. The portion of high-affinity states and the influence of guanine nucleotides were most pronounced at 22 degrees C. Only low-affinity states could be detected in pertussis toxin-treated membranes. It is concluded that adenosine receptors in the human ventricle couple via a G protein sensitive to pertussis-toxin. Alterations of the coupling of adenosine receptors might have a pathophysiological role in dilated cardiomyopathy in which pertussis toxin substrates are increased.
用人离体心脏心肌膜中的腺苷受体与放射性标记配体[3H]DPCPX（1,3 - 二丙基 - 8 - 环戊基黄嘌呤）进行标记。激动剂竞争曲线显示出高亲和力和低亲和力状态。添加鸟苷酰亚胺二磷酸（Gpp(NH)p）可使所有受体转变为低亲和力状态。高亲和力状态的比例以及鸟嘌呤核苷酸的影响在22摄氏度时最为明显。在百日咳毒素处理的膜中仅能检测到低亲和力状态。得出的结论是，人心室中的腺苷受体通过对百日咳毒素敏感的G蛋白进行偶联。腺苷受体偶联的改变可能在扩张型心肌病中具有病理生理作用，其中百日咳毒素底物会增加。
