title: [Determination of progesterone and its main metabolite in rat plasma and uterus using HPLC].
abstract: OBJECTIVE
  To quantify progesterone (P) and one of its metabolites 20alpha-hydroxy-4-pregnen-3-one (20alpha-OHP) in rat plasma and uterus after im administration of progesterone.
  
  
  METHODS
  Plasma and uterus samples were prepared by liquid-liquid extraction and separated through Shimadzu VP-ODS column (150 mm x 4.6 mm ID, 5 microm). The mobile phase consisted of acetonitrile and water (60: 40, adjusted to pH 4.0 with phosphoric acid). The detector was set at 240 nm. Norgestrel was used as the internal standard.
  
  
  RESULTS
  Cmax of P in plasma was (508 +/- 62) microg x L(-1), Tmax was (3.2 +/- 0.4) h, T1/2 (ke) was (10 +/- 4) h and mean AUC0-48h was (5886 +/- 1573) microg x L(-1) x h. The maximum concentration of P in uterus was (1.7 +/- 1.1) microg x g(-1) and the peak time was (5.2 +/- 1.11) h. 20alpha-OHP showed a similar Tmax with P.
  
  
  CONCLUSIONS
  The method is accurate and convenient. It can be used to determine P and its main metabolite 20alpha-OHP simultaneously for studying their preclinical pharmacokinetics.
authors.affiliation: West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
authors.forename: Li-wen
authors.initials: LW
authors.lastname: Zhang
authors.forename: Ruo-bing
authors.initials: RB
authors.lastname: Chao
mesh_terms: D004092:20-alpha-Dihydroprogesterone / Q000097:blood / Q000493:pharmacokinetics*; D000818:Animals; D019540:Area Under Curve; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005260:Female; D007273:Injections, Intramuscular; D011374:Progesterone / Q000097:blood / Q000378:metabolism / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D014599:Uterus / Q000378:metabolism*
chemical_list: D004092:20-alpha-Dihydroprogesterone; D011374:Progesterone