Effect of mifepristone on COX-2 both in eutopic and ectopic endometrium in mouse endometriotic model.
OBJECTIVE
To study the influence of mifepristone on the expression of cyclooxygenase 2 (COX-2) protein and COX-2 mRNA and then to evaluate the mechanism.


METHODS
After the establishment of 30 mice endometriosis models, the mice were randomly divided into six groups with 5 mice each group and assigned to experimental and control groups of 1-, 4- and 6-week circle according to whether mifepristone (0.13 mg d(-1)) was taken or not. Small animal optical imaging system was used to detect the fluorescent intensity of the ectopic tissue. Reverse transcript-polymerase chain reaction and western blot was used to examine COX-2 protein and COX-2 mRNA expression. ELISA was used to examine concentration of PGE(2) in serum.


RESULTS
Mifepristone could not affect the fluorescent intensity of the ectopic endometrium after it was taken 1, 4, and 6 (P > 0.05). However, it could decrease the transcription of COX-2 mRNA in the 1 and 4 week groups (P < 0.05), while the difference in the 6 week group was not significant (P > 0.05). It could decrease the expression of COX-2 protein after it was taken 4 and 6 weeks (P < 0.05). The serous PGE(2) in the trial groups was lower than that in the control groups, but the difference was not significant (P > 0.05).


CONCLUSIONS
This study showed that mifepristone could not affect the size of the ectopic endometrium, but it could decrease the transcription of COX-2 gene and then reduce the expression of COX-2 protein and its product PGE(2) which is an important factor which mediate pain. This maybe another mechanism that mifepristone takes effect through anti-inflammatory path.
Department of Gynecology and Obstetrics, Shanghai Fifth Hospital, Shanghai 200240, People's Republic of China.
Xiujuan
X
Li
Yanyan
Y
Bao
Peng
P
Fang
Yaping
Y
Chen
Zhongdong
Z
Qiao
D000818:Animals; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D015232:Dinoprostone / Q000097:blood; D004353:Drug Evaluation, Preclinical; D004715:Endometriosis / Q000188:drug therapy* / Q000473:pathology; D004717:Endometrium / Q000378:metabolism* / Q000473:pathology; D005260:Female; D005453:Fluorescence; D008600:Menstruation-Inducing Agents / Q000494:pharmacology / Q000627:therapeutic use*; D051379:Mice; D008810:Mice, Inbred C57BL; D015735:Mifepristone / Q000494:pharmacology / Q000627:therapeutic use*; D012333:RNA, Messenger / Q000378:metabolism
D008600:Menstruation-Inducing Agents; D012333:RNA, Messenger; D015735:Mifepristone; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D015232:Dinoprostone