title: Ammonia concentration in human preovulatory ovarian follicles.
abstract: OBJECTIVE
  To determine ammonia concentrations in both the direct environment of the oocyte, ovarian follicular fluid, and peripheral blood.
  
  
  METHODS
  Samples of preovulatory follicular fluid and antecubital venous blood were obtained from 23 randomly selected women attending an in vitro fertilization program in an academic department. Ammonia concentrations were measured using the indophenol method.
  
  
  RESULTS
  In every patient examined, the ratio of ammonia concentration in follicular fluid to that in blood exceeded 1.0. Mean ammonia concentration in follicular fluid (38.01+/-2.61 microM) was significantly higher than that in blood (22.70+/-1.35 microM; P<0.001 paired Student's t test).
  
  
  CONCLUSIONS
  There is an ammonia gradient from follicular fluid to blood. The human preovulatory oocyte grows in an environment of a moderately increased ammonia concentration. This study suggests that the preovulatory follicle is a source of ammonia production.
authors.affiliation: Institute of Obstetrics and Gynecology, Białystok Medical University, Skłodowskiej-Curie 24 A, 15-276, Białystok, Poland. jozwik@obgyn.edu.pl
authors.forename: M
authors.initials: M
authors.lastname: Józwik
authors.forename: M
authors.initials: M
authors.lastname: Józwik
authors.forename: S
authors.initials: S
authors.lastname: Wołczyński
authors.forename: M
authors.initials: M
authors.lastname: Jóźwik
authors.forename: M
authors.initials: M
authors.lastname: Szamatowicz
mesh_terms: D000328:Adult; D000641:Ammonia / Q000032:analysis* / Q000097:blood; D000925:Anticoagulants / Q000097:blood; D004492:Edetic Acid / Q000097:blood; D005189:False Positive Reactions; D005260:Female; D015571:Follicular Fluid / Q000737:chemistry*; D006493:Heparin / Q000097:blood; D006801:Humans; D010060:Ovulation
chemical_list: D000925:Anticoagulants; D000641:Ammonia; D006493:Heparin; D004492:Edetic Acid