Göthert M, Schlicker E, Hentrich F, Rohm N, Zerkowski H R
Eur J Pharmacol. 1984 Jul 13;102(2):261-7. doi: 10.1016/0014-2999(84)90257-7.
Strips of human saphenous veins were incubated with [3H]noradrenaline and subsequently superfused with physiological salt solution containing cocaine, corticosterone and propranolol. The electrically (6 Hz) evoked overflow of tritium (78% of which was accounted for by unmetabolized [3H]noradrenaline) was abolished by tetrodotoxin or omission of Ca2+ from the superfusion fluid. Unlabelled noradrenaline, alpha-methylnoradrenaline, B-HT 920 and clonidine inhibited the evoked overflow (maximum effect of clonidine lower than that of the other compounds) whereas methoxamine was ineffective. The alpha 2-adrenoceptor antagonists, BDF 6143 and rauwolscine, facilitated the evoked overflow but no effect was obtained with prazosin. Rauwolscine produced a shift to the right of the concentration-response curve of B-HT 920 for its inhibitory effect on evoked outflow and BDF 6143 caused a shift to the right of the corresponding curve of clonidine. It is concluded that the stimulation-evoked release of noradrenaline from the sympathetic nerve fibres of the human saphenous vein is modulated via presynaptic alpha 2-adrenoceptors.
将人隐静脉条与[3H]去甲肾上腺素一起孵育，随后用含有可卡因、皮质酮和普萘洛尔的生理盐溶液进行灌流。电刺激（6Hz）诱发的氚溢出（其中78%由未代谢的[3H]去甲肾上腺素引起）可被河豚毒素或从灌流液中去除Ca2+所消除。未标记的去甲肾上腺素、α-甲基去甲肾上腺素、B-HT 920和可乐定可抑制诱发的溢出（可乐定的最大效应低于其他化合物），而甲氧明则无效。α2-肾上腺素能受体拮抗剂BDF 6143和萝芙木碱可促进诱发的溢出，但哌唑嗪无此作用。萝芙木碱使B-HT 920对诱发流出的抑制作用的浓度-反应曲线右移，BDF 6143使可乐定的相应曲线右移。结论是人隐静脉交感神经纤维受刺激诱发的去甲肾上腺素释放通过突触前α2-肾上腺素能受体进行调节。
