title: Effects of hypophyseal, placental, hypophysiotropic, and steroid hormones on ovipositor elongation and ovulation in the rose bitterling, Rhodeus ocellatus ocellatus.
abstract: Effects of various hypophyseal, placental, hypophysiotropic, and steroid hormones on ovipositor elongation and ovulation were investigated using the mature female rose bitterling, Rhodeus ocellatus ocellatus. Mammalian LH and HCG were effective at high doses whereas mammalian prolactin, FSH, ACTH, TSH, and neurohypophyseal hormones were ineffective. Synthetic LH-RH had some effects at very high doses. Fish pituitary extracts were much more potent than mammalian gonadotropins and a dose-response curve of elongation was obtained. This suggests that the ovipositor test is a good bioassay for fish gonadotropin. Some C21-steroids, especially 17 alpha-hydroxyprogesterone and 17 alpha-hydroxy-20 beta-dihydroprogesterone, also had prominent effects on ovipositor elongation, indicating the effects of gonadotropins may be via some C21-steroids. Hypophysectomy did not affect the sensitivity to gonadotropin but somewhat reduced the response to steroid. The relationship between the activity of steroids and their structure is discussed.
mesh_terms: D000818:Animals; D003530:Cyprinidae / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D006728:Hormones / Q000494:pharmacology*; D008322:Mammals; D010060:Ovulation / Q000187:drug effects*; D010907:Pituitary Hormones / Q000494:pharmacology; D010926:Placental Hormones / Q000494:pharmacology; D012741:Sexual Maturation / Q000187:drug effects*; D013256:Steroids / Q000494:pharmacology
chemical_list: D006728:Hormones; D010907:Pituitary Hormones; D010926:Placental Hormones; D013256:Steroids; D007987:Gonadotropin-Releasing Hormone