Effect of bromocryptine on 20 alpha-hydroxysteroiddehydrogenase regulation in the corpus luteum of the pregnant rat
Loewit, K.; Kofler, R.; Tabarelli, M.; Schwarz, S.
Acta Endocrinologica 98(1): 133-136
1981
ISSN/ISBN: 0001-5598 PMID: 6945026 Document Number: 172730
Pregnant Sprague Dawley rats were passively immunized with antiserum to bovine luteinizing hormone (anti-LH) on day 10 of pregnancy, and treated with 1 or 1.5 mg/day of the prolactin (Prl) inhibitor bromocryptine (BEC) between days 10-12 or 9-12, respectively. On day 12 a laparotomy was performed to assess the state of pregnancy and to remove the ovaries for histochemical detection of 20.alpha.-hydroxysteroid-dehydrogenase (20.alpha.-OHSD) in the corpora lutea of pregnancy. In a 2nd experiment pregnant rats were treated with 1.5 mg BEC/day from days 17-22, checked for fetal state and ovariectomized on day 22 before giving birth. Treatment with BEC in effective doses did not interfere with anti-LH-induced termination of pregnancy and consequent reappearance of 20.alpha.-OHSD activity on day 12, or with spontaneous recurrence of enzyme activity at the end of gestation. Prl apparently has no direct and immediate role in 20.alpha.-OHSD regulation, at least on day 12, although substitution by endogenous rat placental lactogen at the end of pregnancy cannot be excluded.