Antireproductive effect of a potent LHRH antagonist (Nal-Lys antagonist:antide) during early pregnancy in the rat.
Effects of a potent third generation LHRH antagonist [Nal-Lys antagonist:antide] have been observed during the first half of pregnancy in rats. A daily dose of 40 micrograms or above, when administered from day 8 of pregnancy, suppressed serum progesterone levels within 48 h and by day 12 there was complete absence of live fetuses. Lower doses of antide (10-20 micrograms) reduced progesterone levels in circulation but were unable to induce abortion consistently in all treated rats. Administration of 150 or 300 micrograms of antide once on day 8 suppressed the progesterone levels within 24 h. Only a dose of 300 micrograms was effective in completely interfering with gestation by day 12 with no observable live fetuses.
Srivastava
R K
RK
Department of Physiology, Morehouse School of Medicine, Atlanta, Georgia 30310-1495.
Sridaran
R
R
D000818:Animals; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D009842:Oligopeptides / Q000008:administration & dosage / Q000494:pharmacology*; D009929:Organ Size / Q000187:drug effects; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000187:drug effects*; D011374:Progesterone / Q000097:blood / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014599:Uterus / Q000187:drug effects
D009842:Oligopeptides; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; C057022:iturelix