Breschi M C, Martinotti E, Ducci M, Fantoni B
Istituto Policattedra di Discipline Biologiche, Facoltá di Farmacia, Universitá di Pisa, Italy.
Pharmacol Res Commun. 1987 Jun;19(6):415-27. doi: 10.1016/0031-6989(87)90081-6.
The activities of the alpha-1 antagonist prazosin and alpha-2 antagonist yohimbine were evaluated against noradrenaline (NA), methoxamine (Me) and clonidine (Clo) on the reserpinized rat vas deferens. Prazosin antagonized competitively Me but not NA and Clo. On the other hand yohimbine showed a low and not competitive antagonism towards all the three agonists. Similar results were obtained when the antagonistic activities were tested in the presence of the alternative antagonist, in the attempt to isolate a single receptor population. We can conclude that the smooth musculature of the rat vas deferens contains prevalently alpha-1 adrenoceptors and a small population of NA activated receptors resistant to alpha-2 antagonists.
在利血平化的大鼠输精管上，评估了α1拮抗剂哌唑嗪和α2拮抗剂育亨宾对去甲肾上腺素（NA）、甲氧明（Me）和可乐定（Clo）的作用。哌唑嗪竞争性拮抗Me，但不拮抗NA和Clo。另一方面，育亨宾对所有三种激动剂表现出低水平且非竞争性的拮抗作用。当在另一种拮抗剂存在的情况下测试拮抗活性以试图分离单一受体群体时，获得了类似的结果。我们可以得出结论，大鼠输精管的平滑肌组织主要含有α1肾上腺素能受体以及一小部分对α2拮抗剂有抗性的NA激活受体。
