Objective: To explore the expression of renin-angiotensin system component (ACE-AngII-AT1/AT2 & ACE2-Ang-(1-7)-Mas) in endometrium of polycystic ovary syndrome (PCOS) patients and normal controls.
Methods: Thirty cases of normal endometrium in proliferative and secretory phases respectively were selected for the protein levels of AngII, AT1, AT2, ACE2, Ang-(1-7) and Mas through immunohistochemistry. And the specimens of proliferative endometrium from 15 PCOS patients and 15 normal controls respectively were prepared for the expressions of AT1, AT2, ACE2 and Mas mRNA through relative quantitative -polymerase chain reaction (RQ-PCR). The histological phases of endometria were confirmed by hematoxylin & eosin staining under microscope.
Results: The expressions of AngII, AT1R, AT2R, ACE2, Ang-(1-7) and Mas showed periodical changes in endometrium throughout normal menstrual cycles and shared a similar trend. The expression was more pronounced in epithelial cells than that in stromal cells while it was also more dramatic in secretory phase than proliferative phase; The mRNA expressions of AT1, AT2, ACE2 and MAS were higher in PCOS endometrium than those in normal controls. Statistically significant differences existed between two groups (P < 0.01).
Conclusions: There is local existence of RAS in endometrium; Increased expressions of AT1 mRNA, AT2 mRNA, ACE2 mRNA and Mas mRNA in endometrium of PCOS may influence endometrial development and play a role in the pathological process of PCOS.