Catecholestrogens and induction of sexual behavior in the ovariectomized rat.
The ability of the catecholestrogens, 4-hydroxyestradiol (4-OHE2) and 2-hydroxyestradiol (2-OHE2) to induce lordosis in ovariectomized rats primed with progesterone was assessed following either short- or long-term exposure to the steroids. 4-OHE2 successfully induced lordosis whether administered as two bolus intrajugular injections separated by a 3-hour interval or continuously for 7 days via subcutaneously implanted osmotic minipumps. 2-OHE2, however, was ineffective under both conditions. When administered subcutaneously in conjunction with 3 days of estradiol benzoate (E2B) treatment, neither of the catecholestrogens exhibited any antiestrogenic effect as compared with the lordosis response to E2B alone. Likewise, simultaneous administration of 2-OHE2 did not significantly alter the response to intrajugular injections of estradiol (E2) or 4-OHE2. The results indicate that 4-OHE2 (but not 2-OHE2) mimicks the lordosis-inducing action of E2 and that neither catecholestrogen has any antiestrogenic effect in this behavioral test system.
D000818:Animals; D002369:Castration; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D002393:Estrogens, Catechol; D005260:Female; D009929:Organ Size / Q000187:drug effects; D011187:Posture; D011374:Progesterone / Q000494:pharmacology; D051381:Rats; D012726:Sexual Behavior, Animal / Q000187:drug effects*
D002393:Estrogens, Catechol; D011374:Progesterone; D004958:Estradiol; C001390:2-hydroxyestradiol; C014036:4-hydroxyestradiol