THE PRESENCE OF CHORIONIC-GONADOTROPIN BETA-SUBUNIT IN NORMAL CYCLIC HUMAN ENDOMETRIUM

The aim of the present study was to determine whether human endometria l cells are able to secrete beta-chorionic gonadotrophin (beta CG). Im munohistochemical studies and in-situ hybridization were performed in order to provide evidence for the occurrence of beta CG in the normal endometrium in 15 patients in the proliferative phase, two patients in the periovulatory phase and 13 patients in the secretory phase. Neith er immunohistochemical nor hybridization reactions could be recognized during the proliferative phase. In contrast, both protein and beta CG mRNA were observed in the glandular cells of the endometrium during t he secretory phase. The results were supported by Western blotting of secretory phase endometrium extracts and the assessment of the functio nal secretory capacity of primary endometrium cultures. In comparison with cultured and separated cell fractions, tissue extracts showed a h igher beta CG, indicating a regulatory interaction. In conclusion, bet a CG can be demonstrated in normal human cyclic endometrium, suggestin g a paracrine role in endometrial physiology.