Vol. 100, No. 2,1981 May 29, 1981 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS Pages 769~777 IN VITRO EFFECT OF PROSTAGLANDINS ON CORTICOSTERONE AND ALDOSTERONE PRODUCTION BY FROG INTERRENAL GLAND. Catherine Delarue, Isabelle Perroteau, Fran§ois Leboulenger, Pierre Netchitailo, Philippe Leroux, Sylvie Jggou, Alain Bglanger~, Marie-Christine Tonon and Hubert Vaudry. Groupe de Recherche en Endocrinologie Mol~culaire, ERA CNRS 891, Laboratoire d'Endocrinologie, Facultg des Sciences, 76130 - Mont-Saint-Aignan, France and ¶Centre de Recherche en Endocrinologie Mol~culaire, Le Centre Hospitalier de l'Universit~ Laval, Boulevard Laurier, Qugbec, GIV 4G2 Canada. Received April 7,1981 SUMMARY. In order to elucidate the role of prostaglandins of the E and F series on adrenal steroidogenesis, we have studied corticosterone and aldosterone production by frog interrenal. Rana ridibunda interrenal dice were perifused with amphibian culture medium for ten hours. Corticosterone and aldosterone concentrations were measured in the effluent perifusate using sensitive and specific radioirmnunoassay methods. Perifusion of interrenal fragments with increasing concentrations of PGE 1 and PGE 2 (ranging from 8.8 nM to 2.8 ~M)led to a dose-related increase in both corticosterone and aldosterone biosynthesis, the magnitude of the stimulation being 1.3 fold higher for aldosterone than for corticosterone. High concentrations of PGF2~ (2.8 ~M) were only responsible for a slight increase in corticosteroid biosynthesis while PGFI~ was almost inactive. Indomethacin an inhibitor of prostaglandin biosynthesis caused a marked decrease of spontaneous production of corticosterone (-84%) and aldo- sterone (-75%) but did not alter the stimulation of steroidogenesis induced by ACTH. From these data, it was concluded that ]) exogenous prostaglandins control cortieosteroid production in amphibia ; 2) endogenous prostaglandins are required for spontaneous biosynthesis of corticosteroids ; 3) endogenous prostaglandins are not involved in ACTH-induced steroidogenesis. The studies which have been designated to investigate the role of prosta- glandins (PGs) in the regulation of adrenocortical steroidogenesis have yield- ed to conflicting results. According to the type of PGs used, to the animals studied and to the technique employed, both inhibition (]), non stimulation (2, 3) and stimulation (4-6) have been reported. Concurrently, controversial results have been obtained with indomethacin (IDM), a potent inhibitor of PG synthesis. Gallant and Brownie (2) have shown that, in vivo, IDM does not 0006-291×/81/100769-09501.00/0 Copyr~ht © 1981byAcademtc Press, ~c. 769 AHrigh~ofreproduct~nin anyform reserved.