Alabaster V A, Keir R F, Peters C J
Naunyn Schmiedebergs Arch Pharmacol. 1985 Jul;330(1):33-6. doi: 10.1007/BF00586706.
The alpha adrenoceptors present on the saphenous vein of the dog and rabbit were characterised in vitro using the selective alpha 1 antagonist prazosin and the alpha 2 antagonists rauwolscine and yohimbine. In the dog saphenous vein, prazosin and rauwolscine competitively antagonised contractile responses to phenylephrine and UK-14,304 respectively. Noradrenaline was competitively blocked by prazosin only. In contrast, phenylephrine and methoxamine-induced responses in the rabbit saphenous vein were insensitive to prazosin and corynanthine. Rauwolscine competitively blocked responses to UK-14,304, noradrenaline and phenylephrine and pA2 values were similar against each agonist. Noradrenaline and UK-14,304 were equipotent agonists on the rabbit saphenous vein while in the dog vein noradrenaline has a lower potency than UK-14,304. These results suggest that the dog saphenous vein has a mixed population of alpha adrenoceptors, while the alpha adrenoceptors on the rabbit vein are homogeneous, with characteristics of the alpha 2 subtype.
利用选择性α1拮抗剂哌唑嗪以及α2拮抗剂育亨宾和萝芙素，在体外对犬和兔隐静脉上的α肾上腺素能受体进行了特性研究。在犬隐静脉中，哌唑嗪和萝芙素分别竞争性拮抗对去氧肾上腺素和UK-14,304的收缩反应。去甲肾上腺素仅被哌唑嗪竞争性阻断。相比之下，去氧肾上腺素和甲氧明在兔隐静脉中诱导的反应对哌唑嗪和育亨宾不敏感。萝芙素竞争性阻断对UK-14,304、去甲肾上腺素和去氧肾上腺素的反应，并且对每种激动剂的pA2值相似。去甲肾上腺素和UK-14,304在兔隐静脉上是等效激动剂，而在犬静脉中去甲肾上腺素的效力低于UK-14,304。这些结果表明，犬隐静脉具有混合的α肾上腺素能受体群体，而兔静脉上的α肾上腺素能受体是同质的，具有α2亚型的特征。
