Arnold-Reed D E, Balment R J
School of Biological Sciences, University of Manchester, United Kingdom.
Gen Comp Endocrinol. 1994 Oct;96(1):85-91. doi: 10.1006/gcen.1994.1161.
Adrenocorticotrophic hormone (ACTH), angiotensin II (AII), and the urophysial peptides, urotensins I and II (UI and UII), stimulate cortisol secretion by interrenal preparations of seawater (SW) and freshwater (FW) adapted trout. Steroid secretion was not disturbed in sham-treated control groups. The increased cortisol secretion following perifusion of tissue with 10(-7) M ACTH in combination with 10(-7) M AII, 10(-7) M UI, or 10(-7) M UII was greater than after separate administration of ACTH, AII, UI, or UII. These responses were no greater than the summation of the separate effects of ACTH, AII, or UII in SW and FW derived tissue or of ACTH and UI in FW derived tissue. However, the increased cortisol secretion (600-700%) after UI and ACTH in combination in SW adapted fish was significantly higher than the summated responses (100-200%) to UI and ACTH when administered separately. These results suggest that in SW fish interrenal UI enhances the steroidogenic action of ACTH, a potentially important response in SW teleost fish.
促肾上腺皮质激素（ACTH）、血管紧张素II（AII）以及尿体激肽，即尿紧张素I和II（UI和UII），可刺激适应海水（SW）和淡水（FW）的虹鳟鱼肾间组织分泌皮质醇。假手术处理的对照组中，类固醇分泌未受干扰。用10⁻⁷ M ACTH与10⁻⁷ M AII、10⁻⁷ M UI或10⁻⁷ M UII联合灌注组织后，皮质醇分泌增加量大于单独给予ACTH、AII、UI或UII后的增加量。这些反应不大于ACTH、AII或UII对SW和FW来源组织的单独作用之和，也不大于ACTH和UI对FW来源组织的单独作用之和。然而，在适应SW的鱼类中，UI与ACTH联合使用后皮质醇分泌增加（600 - 700%），显著高于单独给予UI和ACTH时的累加反应（100 - 200%）。这些结果表明，在SW鱼类中，肾间UI增强了ACTH的类固醇生成作用，这在SW硬骨鱼中可能是一个重要反应。
