用~3H-prazosin 与~3H-rauwolscine 结合从狗大隐静脉分离出富含质膜的微粒体部分来研究突触后α受体亚型。Bmax,~3H-rauwolscine 4倍高于~3H-prazosin。两放射性配体Kα值,在饱和实验中与动力学实验中相一致。竞争实验显示两种不同的结合部位。α_1受体激动剂 phenylephrine 与两放射性配体有相同亲和力,而α_2受体激动剂 B-HT920示不同亲和力。本文表明狗大隐静脉质膜上存在两类α受体拮抗剂的结合部位。 Using the combination of ~3H-prazosin with ~3H-rauwolscine, the plasma membrane-rich microsomes were isolated from the dog saphenous vein to study the postsynaptic alpha receptor subtype. Bmax, ~3H-rauwolscine was 4 times higher than ~3H-prazosin. The value of the two radioligand Kα was consistent with the kinetic experiments in saturation experiments. Competition experiments show two different binding sites. The alpha 1 receptor agonist phenylephrine has the same affinity for both radioligands, and the alpha 2 receptor agonist B-HT920 shows different affinities. This article shows that there are two types of binding sites for alpha-receptor antagonists on the plasma membrane of dogs.