[The effect of mifepristone on progesterone and estrogen receptors in human decidua and serum hormone levels].
OBJECTIVE
To examine the effects of mifepristone on progesterone and estrogen receptors in human decidua and steroid hormone levels in serum for investigating the mechanisms of antigestational action of mifepristone.


METHODS
Decidual progesterone receptor (PR) and estrogen receptor (ER) concentrations or binding sites were measured by both dextran coated charcoal (DCC) and histochemical methods in normal subjects and after 100 mg-mifepristone treatment. Meanwhile, the concentrations of serum beta-human chorionic gonadotropin (beta-hCG), estradiol (E2), progesterone (P) and testosterone (T) were also determined by radioimmunoassay. The reactions of these two groups were compared.


RESULTS
Mifepristone therapy significantly reduced decidual cytosol PR content (P < 0.05) and increased decidual cytosol ER content (P < 0.05). Histochemical analyses indicated mifepristone treatment increased ER staining in vessel and glandular cells of decidua. The serum beta-hCG, E2 and T levels elevated significantly after mifepristone administration, while the progesterone levels were unaffected.


CONCLUSIONS
Our data suggested that the anti-gestational effect of mifepristone may act through decreasing the decidual PR and increasing the ER concentrations, which interfered the balance between these two components, and also through increasing serum T levels.
Zhang
J
J
Gynecological and Obstetrical Hospital, Shanghai Medical University.
Zhou
J
J
Lu
X
X
D000021:Abortifacient Agents, Steroidal / Q000494:pharmacology*; D000328:Adult; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D003656:Decidua / Q000378:metabolism*; D005260:Female; D006801:Humans; D015735:Mifepristone / Q000494:pharmacology*; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D011960:Receptors, Estrogen / Q000187:drug effects*; D011980:Receptors, Progesterone / Q000187:drug effects*; D013739:Testosterone / Q000097:blood*
D000021:Abortifacient Agents, Steroidal; D018997:Chorionic Gonadotropin, beta Subunit, Human; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D015735:Mifepristone; D013739:Testosterone; D011374:Progesterone