title: Circulating levels of nitric oxide in fertile women in relation to the menstrual cycle.
abstract: OBJECTIVE
  To investigate nitric oxide (NO) production in the two phases of normal menstrual cycle.
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  Normal human volunteers in an academic research environment.
  
  
  METHODS
  Fifteen normally cycling women.
  
  
  METHODS
  Follicle growth monitoring by ultrasound, serum, and plasma sampling in the midfollicular phase, at ovulation, and in the midsecretory phase.
  
  
  METHODS
  Plasma concentration of NO stable oxidation products and serum concentrations of E2 and P.
  
  
  RESULTS
  Plasma concentration of NO metabolites resulted higher in the follicular phase with respect to the secretory phase and peaked at midcycle.
  
  
  CONCLUSIONS
  The results strongly support the existence of an E2 control of NO production and release. The significant reduction in NO metabolites observed in the secretory phase suggests a possible opposing action of P on either NO production or release.
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: P
authors.initials: P
authors.lastname: Galantino
authors.forename: G
authors.initials: G
authors.lastname: Balzano
authors.forename: L M
authors.initials: LM
authors.lastname: Schonauer
mesh_terms: D000328:Adult; D004958:Estradiol / Q000097:blood; D005260:Female; D005298:Fertility; D005498:Follicular Phase / Q000097:blood; D006801:Humans; D008597:Menstrual Cycle / Q000097:blood*; D008875:Middle Aged; D009569:Nitric Oxide / Q000097:blood* / Q000378:metabolism; D009994:Osmolar Concentration; D010084:Oxidation-Reduction; D011446:Prospective Studies
chemical_list: D009569:Nitric Oxide; D004958:Estradiol