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.

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 PGE2 in serum. Result(s) 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). It could decrease the expression of COX-2 protein after it was taken 4 and 6 weeks (P 0.05). Conclusion(s) 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 PGE2 which is an important factor which mediate pain. This maybe another mechanism that mifepristone takes effect through anti-inflammatory path. Similar content being viewed by others

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