Castro M G, Morano M I, Estivariz F E, Iturriza F C
Acta Physiol Pharmacol Latinoam. 1986;36(4):347-57.
We have pursued with the characterization of ACTH secretagogues from the avian corticomelanotrophic (CM) cell, by testing the ACTH-releasing activity of various monoamines and related drugs, using an in vitro system which uses dispersed perfused duck pituitary cells. The substances used were: noradrenaline (NA), adrenaline (A), dopamine (DA), serotonin (5-HT), phenylephrine (Phe), and isoproterenol (IP). The responses obtained with the substances assayed were compared with those obtained with dilutions of duck median eminence extracts (DME). The order of "intrinsic activities" was: NA = A greater than Phe greater than IP greater than DA = 5-HT. The substances were tested within the range 10(-9)-10(-4) M. All substances tested behaved as partial agonists with respect to DME. The "intrinsic activity" (Vmax) of the most potent agonists tested, A and NA, was 0.66 of that obtained with DME. It is concluded that in the duck, the CM cells secrete ACTH in response to A and NA (and other pharmacological substances) at doses which are compatible with a physiological role of those catecholamines acting directly upon the CM cell of the avian adenohypophysis. 5-HT and DA behaved as very weak agonists in stimulating ACTH release from duck CM cells in the system employed.
我们通过使用一种体外系统，该系统采用分散灌流的鸭垂体细胞，来测试各种单胺类物质及相关药物的促肾上腺皮质激素（ACTH）释放活性，从而对来自鸟类促肾上腺皮质黑素细胞（CM）的ACTH促分泌素进行了表征研究。所使用的物质有：去甲肾上腺素（NA）、肾上腺素（A）、多巴胺（DA）、血清素（5-羟色胺，5-HT）、苯肾上腺素（Phe）和异丙肾上腺素（IP）。将所测物质获得的反应与鸭正中隆起提取物（DME）稀释液获得的反应进行比较。“内在活性”顺序为：NA = A ＞ Phe ＞ IP ＞ DA = 5-HT。这些物质在10⁻⁹ - 10⁻⁴ M范围内进行测试。所有测试物质相对于DME而言均表现为部分激动剂。所测试的最有效激动剂A和NA的“内在活性”（Vmax）是DME的0.66倍。得出的结论是，在鸭体内，CM细胞对A和NA（以及其他药理物质）的反应是分泌ACTH，其剂量与这些儿茶酚胺直接作用于鸟类腺垂体CM细胞的生理作用相一致。在所用系统中，5-HT和DA在刺激鸭CM细胞释放ACTH方面表现为非常弱的激动剂。
