Effects of aromatase inhibitors on in vitro steroidogenesis by Atlantic salmon (Salmo salar) gonadal and brain tissue.
In order to assess the efficacy of selected aromatase inhibitors on Atlantic salmon (Salmo salar) ovarian and brain tissue, in vitro systems were developed for measuring 17beta-estradiol (E(2)) production by these tissues. Isolated vitellogenic follicles, or homogenised whole brains were incubated at 10 degrees C in complete Cortlands solution for 18 or 42 h respectively, and E(2) levels in the medium were determined by RIA. The addition of testosterone to the medium increased E(2) production in all preparations. E(2) production by whole brain homogenate was reduced by co-incubation with the aromatase inhibitors 1,4,6-androstatriene-3,17-dione (ATD), 4-androstene-4-ol-3,17-dione (OHA), aminoglutethimide, fadrozole or miconazole. Fadrozole, ATD, and OHA reduced E(2) production by vitellogenic follicles at a medium concentration of 0.1 microg mL(-1), whereas miconazole was only effective at 10 microg mL(-1). This study demonstrates a simple and rapid screening method for assessing the efficacy of aromatase inhibitors on fish tissues, and that the aromatase inhibitors ATD, OHA and fadrozole are potent inhibitors of both brain and gonadal aromatase in vitro, in Atlantic salmon.
Lee
Peter S
PS
School of Aquaculture, Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Locked Bag 1370, Launceston, Tasmania 7250, Australia. p.lee@niwa.co.nz
Pankhurst
Ned W
NW
King
Henry R
HR
D000616:Aminoglutethimide / Q000494:pharmacology; D000733:Androstatrienes / Q000494:pharmacology; D000735:Androstenedione / Q000494:pharmacology; D000818:Animals; D047072:Aromatase Inhibitors / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D004958:Estradiol / Q000096:biosynthesis*; D017316:Fadrozole / Q000494:pharmacology; D005260:Female; D008825:Miconazole / Q000494:pharmacology; D006080:Ovarian Follicle / Q000187:drug effects / Q000378:metabolism; D020317:Salmo salar / Q000378:metabolism*; D013739:Testosterone / Q000494:pharmacology
D000733:Androstatrienes; D047072:Aromatase Inhibitors; D000616:Aminoglutethimide; C011658:androsta-1,4,6-triene-3,17-dione; D013739:Testosterone; D000735:Androstenedione; D004958:Estradiol; D008825:Miconazole; D017316:Fadrozole