title: Effects of estrogen and progesterone on platelet-activating factor acetylhydrolase activity in ovariectomised rats.
abstract: OBJECTIVE
  To evaluate the effect of estrogen and progesterone on plasma platelet-activating factor acetylhydrolase (PAF-AH) activity in ovariectomized rats.
  
  
  METHODS
  Plasma PAF-AH activity was examined in ovariectomized rats treated with 17 alpha-ethynylestradiol (0.25 mg/kg; 6 days) or medroxyprogesterone (50 mg/kg; 6 days). The intra- and inter-assay coefficients of variation for plasma PAF-AH activity were 2.5% and 4.4%, respectively. Plasma lipoprotein profiles on day 5 were determined with commercially available kits.
  
  
  RESULTS
  Ovariectomized rats showed no significant change in plasma PAF-AH activity over a 14 day period. Estrogen decreased the PAF-AH activity up to 85%, and progesterone increased PAF-AH activity up to 44% in ovariectomized rats. There was a positive correlation between plasma PAF-AH activity and high density lipoprotein cholesterol (r = 0.96, p < 0.001).
  
  
  CONCLUSIONS
  These data suggest that estrogen and progesterone exert an effect on plasma PAF-AH activity in ovariectomized rats, possibly via high density lipoprotein cholesterol.
authors.affiliation: Department of Obstetrics and Gynecology, Kumamoto University School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ohshige
authors.forename: M
authors.initials: M
authors.lastname: Ito
authors.forename: H
authors.initials: H
authors.lastname: Koyama
authors.forename: T
authors.initials: T
authors.lastname: Maeda
authors.forename: T
authors.initials: T
authors.lastname: Yoshimura
authors.forename: H
authors.initials: H
authors.lastname: Okamura
mesh_terms: D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase; D000818:Animals; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004997:Ethinyl Estradiol / Q000494:pharmacology*; D005260:Female; D007700:Kinetics; D016018:Least-Squares Analysis; D008074:Lipoproteins / Q000097:blood; D008525:Medroxyprogesterone / Q000494:pharmacology*; D010052:Ovariectomy; D010741:Phospholipases A / Q000097:blood* / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D008074:Lipoproteins; D014280:Triglycerides; D004997:Ethinyl Estradiol; D002784:Cholesterol; D010741:Phospholipases A; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase; D008525:Medroxyprogesterone