Altered progesterone/estrogen receptor ratios in endometriosis: A comparative study of steroid receptors and morphology in endometriosis and endometrium

Publisher Website
Google Scholar
Abstract
In a comparative study of endometriosis and endometrium, specimens were taken from both endometriotic and endometrial tissue in 14 patients. Receptor assays and histological examinations were performed on both specimens. Cy‐tosolic estrogen receptors (ERc) as well as cytosolic progesterone receptors (PRc) were detected in 9/14 and 12/12 cases of endometriosis respectively. Nuclear estrogen receptors (ERn) were detected in 4/4 cases of endometrosis. Expressed as fmol/mg cytosol protein, significantly higher values of both ERc and PRc were found in endometrium than endometriosis (p<0.01). However, when the ratio between PRc and ERc was considered, significantly higher PRc/ERc ratios were found in the cytosol of endometriotic tissue (p<0.01). Thus the lower receptor concentrations found in endometriosis cannot be explained solely as ectopic endometrium being diluted by non‐receptor‐containing tissue. In spite of high PRc/ERc ratios in endometriosis, secretory changes similar to those found in endometrium were observed in only one of 7 cases (p<0.05).