title: A comparison of the pregnancy-terminating potencies of three anti-progestins in guinea-pigs, and the effects of sulprostone.
abstract: The anti-progestins mifepristone, lilopristone (ZK 98734) and HRP 2000 were equipotent at terminating the pregnancy of guinea-pigs during mid-gestation, although mifepristone was more effective at low doses. Sulprostone administration on the day following anti-progestin treatment tended to increase the effectiveness of mifepristone and HRP 2000, without affecting the time interval between the start of the anti-progestin treatment and the day of abortion. It is concluded that, of the three afferent anti-progestins used, none is more potent than the other two at terminating pregnancy in the animal model used. The co-administration of a prostaglandin E2 (PGE2) analogue tends to increase the effectiveness of the anti-progestin.
authors.affiliation: Department of Pharmacology, University of Edinburgh Medical School, Scotland, UK.
authors.forename: N L
authors.initials: NL
authors.lastname: Poyser
authors.forename: M L
authors.initials: ML
authors.lastname: Forcelledo
mesh_terms: D000019:Abortifacient Agents / Q000008:administration & dosage; D000021:Abortifacient Agents, Steroidal / Q000008:administration & dosage; D000028:Abortion, Induced / Q000379:methods*; D000818:Animals; D015232:Dinoprostone / Q000008:administration & dosage / Q000031:analogs & derivatives; D004353:Drug Evaluation, Preclinical; D004357:Drug Synergism; D004963:Estrenes / Q000008:administration & dosage; D005260:Female; D006168:Guinea Pigs; D015735:Mifepristone / Q000008:administration & dosage; D009649:Norpregnadienes; D011247:Pregnancy; D011282:Pregnenediones / Q000008:administration & dosage; D011372:Progestins / Q000037:antagonists & inhibitors*
chemical_list: D000019:Abortifacient Agents; D000021:Abortifacient Agents, Steroidal; D004963:Estrenes; D009649:Norpregnadienes; D011282:Pregnenediones; D011372:Progestins; D015735:Mifepristone; C048260:lilopristone; C016767:sulprostone; C094854:ulipristal; D015232:Dinoprostone