The use of cultured ovarian fragments to assess toxicant alterations in steroidogenesis in the sprague-dawley rat

• Published in: Reproductive toxicology (Elmsford, N.Y.) N.Y.), 1995-03, Vol.9 (2), p.131-141
• Main Authors: Laskey, John W., Berman, Ezra, Ferrell, Janet M.
• Format: Article
• Language: English
• Subjects: aminoglutethimide; Aminoglutethimide - toxicity; Analysis of Variance; Animals; Aromatase - metabolism; Biological and medical sciences; Chorionic Gonadotropin - pharmacology; Chromatography, High Pressure Liquid; Culture Techniques; Embryology: invertebrates and vertebrates. Teratology; Estradiol - biosynthesis; Estradiol - blood; estrous cycle; Estrus - metabolism; Female; Follicle Stimulating Hormone - blood; Fundamental and applied biological sciences. Psychology; Gonadal Steroid Hormones - biosynthesis; Gonadal Steroid Hormones - blood; Humans; Luteinizing Hormone - blood; Ovary - drug effects; Ovary - metabolism; ovary culture; Proestrus; Progesterone - biosynthesis; Progesterone - blood; Radioimmunoassay; Rats; Rats, Sprague-Dawley; Reference Values; Reproducibility of Results; steroidogenesis; Teratology. Teratogens; Testosterone - biosynthesis; Testosterone - blood
• ISSN: 0890-6238; 1873-1708
• DOI: 10.1016/0890-6238(95)00063-1

This study was conducted to determine the utility of using steroid production by cultured ovarian fragments to assess toxicant-induced alterations in ovarian steroidogenesis in Sprague-Dawley rats. To this end, serum steroid concentration and steroid production (progesterone (P 4), testosterone (T), estradiol (E 2) > by cultured ovarian fragments is described during a normal 4-day estrous cycle. This culture system was then used to profile the effects of aminoglutethimide shown to have two sites of steroidogenic inhibition, side chain cleavage enzyme and aromatase. LH, FSH, P 4, and E 2 concentrations in serum during the 4-day estrous cycle confirmed that described in the literature for untreated rats. All of the steroids measured had peak production levels during proestrus. The patterns of P 4 and E 2 production by the ovaries in an unstimulated culture mimics that seen in serum. Stimulation with hCG (100 mIU/mL) after the initial l h culture tends to even out the production of P 4, while T production rises faster and peaks earlier. The pattern and levels of estradiol production in hCG-stimulated cultures are very similar to those in the unstimulated culture, both in pattern and in production levels. When cultured ovarian fragments from proestrous rats were treated in vitro with aminoglutethimide (1 to 16 μM), the pattern of steroid production that characterized the inhibitory effects were similar to those reported in the literature using isolated cell culture procedures. This pattern showed a rapid decrease in E 2 production (IC 50 of 2.43 μM), a concurrent rise in T production, and a decrease in P 4 production (IC 50 of 15.5 μM). This culture system is an appropriate system to rapidly assess toxicant effects on ovarian steroidogenesis following in vivo or in vitro exposure.