title: Effect of estrogen replacement therapy on natural killer cell activity in postmenopausal women.
abstract: OBJECTIVE
  To evaluate the impact of menopause and estradiol substitution on natural killer cell activity.
  
  
  METHODS
  Natural killer cell activity and antibody-dependent cellular cytotoxicity were measured in peripheral blood of 53 postmenopausal and 20 premenopausal women in an interval of 3 weeks. Postmenopausal patients were randomly assigned to receive either estradiol valerate (2 mg daily) orally (n = 18), estradiol (50 micrograms/24 h) transcutaneously (n = 18) or no substitution (n = 17), and the testing was repeated 3 weeks later.
  
  
  RESULTS
  Natural killer cell activity but not antibody-dependent cellular cytotoxicity was significantly (P < 0.01) higher in unsubstituted postmenopausal compared to premenopausal subjects. Natural killer cell activity decreased both in orally and transcutaneously estradiol-treated patients (mean [S.D.] before vs. after 3 weeks; oral: 60.8 [9.2]% vs. 52.8 [8.2]% P < 0.01; transcutaneous: 61.5 [10.6]% vs. 54.3 [9.1]% P < 0.01; no substitution: 60.6 [10.6]% vs. 59.3 [8.9]% P > 0.1), whereas antibody-dependent cellular cytotoxicity showed no changes. The addition of 0.1 to 10 ng/ml estradiol to peripheral blood mononuclear cells of untreated postmenopausal women in vitro had no influence upon natural killer cell activity.
  
  
  CONCLUSIONS
  Postmenopausal women receiving no estrogen replacement exhibited an increased natural killer cell activity which decreased during estrogen substitution.
authors.affiliation: Department of Gynecologic Endocrinology, General Hospital, University of Vienna, Austria.
authors.forename: A E
authors.initials: AE
authors.lastname: Albrecht
authors.forename: B W
authors.initials: BW
authors.lastname: Hartmann
authors.forename: C
authors.initials: C
authors.lastname: Scholten
authors.forename: J C
authors.initials: JC
authors.lastname: Huber
authors.forename: W
authors.initials: W
authors.lastname: Kalinowska
authors.forename: C C
authors.initials: CC
authors.lastname: Zielinski
mesh_terms: D000279:Administration, Cutaneous; D000284:Administration, Oral; D000328:Adult; D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects* / Q000276:immunology; D002979:Climacteric / Q000187:drug effects* / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D008875:Middle Aged
chemical_list: D004958:Estradiol