title: Acute effects of transdermal estradiol administration on plasma levels of nitric oxide in postmenopausal women.
abstract: OBJECTIVE
  To investigate the acute effects of transdermal E2 administration on nitric oxide (NO) plasma levels in postmenopausal women.
  
  
  METHODS
  Randomized, placebo-controlled trial.
  
  
  METHODS
  Normal human volunteers in an academic research environment.
  
  
  METHODS
  Twenty healthy postmenopausal women.
  
  
  METHODS
  Transdermal administration of 100 micrograms/d E2 or placebo.
  
  
  METHODS
  Plasma concentrations of NO stable oxidation products and serum concentrations of E2 were assessed before and 24 hours after the administration.
  
  
  RESULTS
  In the group treated with E2 mean concentration of NO metabolites 24 hours after patch application (37.31 +/- 7.62 mumol/L) resulted significantly higher than baseline (21.04 +/- 5.71 mumol/L) and the control group (23.50 +/- 4.03 mumol/L). The correlation between the mean percent increase in NO metabolites and absolute E2 concentrations 24 hours after the E2 administration was statistically significant.
  
  
  CONCLUSIONS
  Transdermal administration of E2 to healthy postmenopausal women increases the plasma levels of NO and this supports the hypothesis that a NO-related mechanisms may contribute to the cardiovascular protective effect of estrogens in postmenopause.
authors.affiliation: Department of Obstetrics and Gynecology, University of Bari, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Cicinelli
authors.forename: L J
authors.initials: LJ
authors.lastname: Ignarro
authors.forename: M
authors.initials: M
authors.lastname: Lograno
authors.forename: G
authors.initials: G
authors.lastname: Matteo
authors.forename: N
authors.initials: N
authors.lastname: Falco
authors.forename: L M
authors.initials: LM
authors.lastname: Schonauer
mesh_terms: D000279:Administration, Cutaneous; D004958:Estradiol / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009569:Nitric Oxide / Q000097:blood*; D017698:Postmenopause / Q000097:blood*
chemical_list: D009569:Nitric Oxide; D004958:Estradiol