Treatment with mifepristone (RU486) and oestradiol facilitates the development of genital septic disease after copulation in female rats.
Ovariectomized female rats were treated with oestradiol and the progesterone-antagonist mifepristone. They allowed males to copulate to a similar extent as ovariectomized rats treated with oestradiol alone. The additional treatment with mifepristone, however, resulted in uterine infections following copulation, together with the prolonged presence of copulatory plugs in the uterine lumen. On several occasions rats became severely ill during the days after copulatory tests, occasionally with lethal consequences. Microscopic examination of the cervix and uterus 1 day after a copulation test in rats treated with oestradiol plus mifepristone, showed that copulatory plugs passed through the cervical canals directly into the uterine lumen. Bacterial infections and local destruction of the uterine epithelium were found in all rats examined. These features were not found in rats treated with oestradiol alone. Actions of mifepristone on the cervix of oestradiol treated rats are likely to play a key role in the passage of copulatory plugs and, thereafter, the development of uterine sepsis.
van der Schoot
P
P
Department of Endocrinology and Reproduction, Faculty of Medicine and Health Sciences, Erasmus University Rotterdam, The Netherlands.
D000818:Animals; D001424:Bacterial Infections / Q000209:etiology* / Q000473:pathology; D003307:Copulation / Q000187:drug effects; D004347:Drug Interactions; D004958:Estradiol / Q000008:administration & dosage*; D005260:Female; D015735:Mifepristone / Q000009:adverse effects*; D010052:Ovariectomy; D051381:Rats; D014591:Uterine Diseases / Q000209:etiology* / Q000473:pathology; D014599:Uterus / Q000187:drug effects* / Q000473:pathology
D015735:Mifepristone; D004958:Estradiol