Effects of RU486 on the Rat Cervix
The progesterone antagonist RU486 induces cervical ripening in several species. The mechanism by which it does so is poorly understood. It is not known if its effects are dependent upon reproductive steroids. Accordingly, this study was conducted to determine the effects of RU486 in the rat cervix in the absence of estrogen and progesterone. We hypothesized that RU486 would not have an effect under these simple hormonal conditions. Female, virgin Sprague-Dawley rats were ovariectomized at day 1 of treatment. Rats were randomly assigned to two treatment groups. Group I (n=3) received 0.4 mL sesame oil vehicle subcutaneously on day 17. Group II (n=3) was treated with 0.4 mL RU486 (8 mg). On day 18 the cervices were removed, trimmed of fat, weighed, and placed in Krebs-Ringer bicarbonate buffer, pH 7.5. Cervical extensibility was determined within 5 hours of tissue collection. There was no significant difference in cervical extensibility between group I and group II. This study provides evidence that RU486's effect on cervical ripening in the rat is mediated either through an estrogen-and/or progesterone-dependent pathway.
School:
St. Mary's University
Department:
Chemistry
Research Advisor:
O. David Sherwood
Department of Research Advisor:
Molecular and Integrative Physiology
Year of Publication:
2003