Progesterone and Pregn-4-en-20α-ol-3-one in Ovarian Venous Blood During Various Reproductive States in the Rat¹

On Circulating Sex Steroids During the Estrous Cycle and the Early Pseudopregnancy in the Rat with Special Reference to its Luteal Activation

“…The levels of sex steroids during pseudopregnancy (PSP) and pregnancy in the rat have been measured mainly in the ovarian venous blood by many investigators (Eto et al, 1962;Fajer and Barraclough, 1967;Hashimoto et al, 1968 ;Yoshinaga et al, 1969 ;Uchida et al, 1970;Shaikh, 1971;Bartosik and Szarowski, 1973). In these studies, however, little attention has been paid on the detailed secretory patterns at the early stage of PSP or pregnancy.…”

Alterations of Ovarian 4-Pregnen-20α-ol-3-one and Adrenal Corticosterone at Various Times after Hypophysectomy, and the Ovarian Response to Exogenous Pituitary Gonadotropin

“…There were, however, no significant differences between these 3 groups (hypox, sham op., intact) in the adrenal corticosterone contents at 30 min after the operation. In contrast to the more progressive decrease of adrenal corticosterone contents from 15 to 120 min in hypox rats than in intact rats, no significant difference was found in the adrenal corticosterone contents between (Greep et al, 1942 ;Creep, 1961 (Hirai et al, 1968c(Hirai et al, , 1969a(Hirai et al, , 1969bHashimoto et al, 1968 …”

Changes in steroidogenesis by isolated rabbit ovarian follicles in vitro during the preovulatory interval with emphasis on active androgen production.

“…In summary, the profile of steroidogenesis qualitatively shifted from Ci9 and C18 steroid production in mature follicles through C21 and C18 steroid production for the first 3 hours, followed by C21 and C19 steroid production between 6 and 9 hours, (Hashimoto et al, 1968;Lindner and Zmigrod, 1967), hamster (Leavitt and Blaha , 1970) and guinea pig (Feder et al ., 1968). The increased production of C21 steroids especially progesterone seems requisite for ovulation, since hCG-induced ovulation is significantly suppressed by blocking the initial rise of progesterone with anti-progesterone antisera in rats as indicated by our recent works (Mori et al, 1977).…”