title: Expression of erythropoietin and erythropoietin receptor in peritoneal endometriosis.
abstract: BACKGROUND
  Recent studies have indicated new physiological roles for erythropoietin (Epo) unrelated to erythropoiesis. We previously demonstrated that the Epo concentrations in peritoneal fluid from patients with stage I endometriosis were significantly higher than those with stages II, III and IV of the disease. Therefore, we hypothesized that Epo may play a role in the pathogenesis of endometriosis, particularly during the early stages of the disease.
  
  
  METHODS
  We investigated the localization of Epo and the Epo receptor (Epo-R) in peritoneal endometriosis and eutopic endometrium, using immunohistochemistry.
  
  
  RESULTS
  We detected Epo and Epo-R localized within glandular epithelial cells in both peritoneal endometriosis and eutopic endometrium. There was no significant difference in Epo expression between red and black peritoneal lesions, whereas Epo-R expression was significantly lower in black peritoneal lesions when compared to red lesions. Epo and Epo-R expression levels within red peritoneal lesions were comparable to those of eutopic endometrium from patients with endometriosis.
  
  
  CONCLUSIONS
  The present findings suggest that Epo may play a role in the pathophysiology of endometriosis.
authors.affiliation: Department of Obstetrics & Gynecology, Tohoku University School of Medicine, 1-1, Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan. SachikoMA@aol.com
authors.forename: Sachiko
authors.initials: S
authors.lastname: Matsuzaki
authors.forename: Michel
authors.initials: M
authors.lastname: Canis
authors.forename: Rei
authors.initials: R
authors.lastname: Yokomizo
authors.forename: Nobuo
authors.initials: N
authors.lastname: Yaegashi
authors.forename: Maurice A
authors.initials: MA
authors.lastname: Bruhat
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Okamura
mesh_terms: D000328:Adult; D004715:Endometriosis / Q000378:metabolism*; D004717:Endometrium / Q000378:metabolism; D004921:Erythropoietin / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D010532:Peritoneal Diseases / Q000378:metabolism*; D017467:Receptors, Erythropoietin / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D017467:Receptors, Erythropoietin; D004921:Erythropoietin