[Expression of leptin and leptin receptor system in woman reproductive organs].

Objective: To explore the expression of leptin, leptin receptor (Ob-R) and related signaling proteins in woman reproductive organs.
Methods: Thirty-nine women, aged 27 - 37, with normal menstrual cycle of which 24 being in proliferative phase and 15 in secretive phase, underwent uterine curettage, to obtain the endometrium. The uterine cervix, vaginal wall, and oviducts were resected from 3 women with hysteromyoma. The expression of mRNA of leptin and long isoform of leptin receptor (Ob-Rb) was detected by in situ hybridization. The expression of leptin and Ob-Rb proteins was examined by immunohistochemical staining. Immunohistochemical staining was used to study the expression of the leptin-related signaling proteins: phosphated signal transducers and activator of transcription (p-STAT3), suppressor of cytokine signaling 3 (SOCS3), and protein inhibitor of activated STAT3 (PIAS3).
Results: The mRNA and protein of leptin and the mRNA and protein of Ob-Rb were expressed in the glands and mesenchyma of endometrium. The expression of Ob-Rb protein was significantly stronger in secretive phase than in proliferative phase (P < 0.01). No significant difference was found between the expression of leptin protein in proliferative phase and that in secretive phase. In the endothelium SOCS3 and PIAS3 were expressed, however, p-STAT3 protein was only weakly expressed or not expressed. Leptin protein and Ob-Rb protein were expressed in the uterine cervix, vagina wall, and epithelium of oviduct, including glands. However, leptin mRNA and Ob-Rb mRNA were only expressed in the ciliated epithelium of oviduct.
Conclusion: Leptin may have an effect on women's reproductive function through leptin receptor systems.