Abstract: Objective：To detect the expression of estrogen receptor (ER) and TrkB in eutopic endometrium and ectopic endometrium in patients with endometriosis, and explore the potential effect of ER and TrkB in the pathogenesis of EMs. Methods：The expressions of ERα, ERβ, TrkB and BDNF in 18 cases with EMs (include 9 proliferating phase cases and 9 secretory phase of eutopic endometrium) were examined using real-time PCR, Western blotting and immunohistochemistry. Results：At mRNA and protein levels, the expression of ERα in eutopic endometrium was higher than ectopic endometrium with endometriosis, while the expression of ERβ and TrkB in eutopic endometrium were lower than ectopic endometrium with endometriosis, all of that difference have statistically significant (P＜0.05). Higher ratio of ERβ/ERα mRNA was found in ectopic endometriosis than eutopic endometrium. In eutopic endometrium, ERα, ERβ and TrkB proteins were mainly expressed in proliferative phase than that in secretory phase (P＜0.05). ERα expression was mainly found in cell nucleus of eutopic endometrium, while ERβ was mainly found in cytoplasm of ectopic endometrium. The expression of ERα and ERβ were more obvious in EMs eutopic endometrium proliferative phase than that in secretory phase. TrkB and BDNF were expressed in both eutopic and ectopic endometrium with EMs, and were mainly expressed in cytoplasm. TrkB was more obvious in proliferative phase eutopic endometrium of EMs. Conclusions：ERβ and TrkB may mediate the pathogenesy of EMs.

Key words: Receptors, estrogen, Receptor, trkB, Endometriosis, Endometrium