title: Plasma adenosine levels increase in women with normal pregnancies.
abstract: OBJECTIVE
  The aim of this study was to investigate plasma adenosine levels during normal pregnancy and to evaluate the possible roles of platelet activation and 5'-nucleotidase as causes of changes in adenosine levels.
  
  
  METHODS
  We measured plasma adenosine levels, the platelet activation markers beta-thromboglobulin and platelet factor 4, and 5'-nucleotidase activity, which catalyzes dephosphorylation from adenosine monophosphate to adenosine, in 34 nonpregnant women and 34 women with normal pregnancies in the third trimester.
  
  
  RESULTS
  The mean plasma adenosine level in pregnant women was 0.59 +/- 0.08 micromol/L (mean +/- SEM), which was significantly higher than that found in nonpregnant women (0.18 +/- 0.04 micromol/L; P <.01). In pregnant women plasma beta-thromboglobulin levels, platelet factor 4 levels, and 5'-nucleotidase activity were significantly higher than in nonpregnant women (P <.05).
  
  
  CONCLUSIONS
  The increase of plasma adenosine may be attributed at least in part to platelet activation and an increase of 5'-nucleotidase activity during normal pregnancy. This increase may be an endogenous compensatory mechanism that diminishes platelet activation and maintains vessel integrity during normal pregnancy.
authors.affiliation: Department of Obstetrics and Gynecology, Nippon Medical School, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yoneyama
authors.forename: S
authors.initials: S
authors.lastname: Suzuki
authors.forename: R
authors.initials: R
authors.lastname: Sawa
authors.forename: Y
authors.initials: Y
authors.lastname: Otsubo
authors.forename: G G
authors.initials: GG
authors.lastname: Power
authors.forename: T
authors.initials: T
authors.lastname: Araki
mesh_terms: D015720:5'-Nucleotidase / Q000097:blood; D000241:Adenosine / Q000097:blood*; D000328:Adult; D005260:Female; D006801:Humans; D010978:Platelet Factor 4 / Q000032:analysis; D011247:Pregnancy / Q000097:blood*; D012016:Reference Values; D001620:beta-Thromboglobulin / Q000032:analysis
chemical_list: D001620:beta-Thromboglobulin; D010978:Platelet Factor 4; D015720:5'-Nucleotidase; D000241:Adenosine