Oestrogen and progesterone influence myometrial and cervical responses at different levels of the mechanisms regulating uterine contractility. One of these mechanisms could involve alterations in the adrenoceptor concentrations. This study was undertaken to assess the effects of treatment with the antiprogestogen RU-486 on the concentrations of α-and β-adrenoceptors in pregnant rabbit myometrial and cervical membranes by means of a radioligand binding technique. The probable relative oestrogen dominance due to the antiprogestogen treatment selectively decreased the α2-adrenoceptor subtype in the cervix, where an α-adrenoceptor dominance was found on day 27 of pregnancy. The results indicate a heterologous regulation of α-adrenoceptors by sex steroids, i.e. suppression of the α2-adrenoceptor concentration by antiprogestogen treatment.
|Number of pages||4|
|Publication status||Published - Nov 1990|
ASJC Scopus subject areas
- Reproductive Medicine
- Obstetrics and Gynaecology