title: Pentobarbital and ketamine suppress serum concentrations of sex hormones in the female rat.
abstract: OBJECTIVE
  To investigate the potential effects of pentobarbital and ketamine on serum concentrations of sex hormones, the present study was performed using pregnant mare serum gonadotropin (PMSG)-primed cyclic female Sprague-Dawley rats.
  
  
  METHODS
  Pentobarbital sodium (37 mg.kg(-1), i. p.) or ketamine-hydrochloride (229 mg.kg(-1), i. m.) was injected 2 and 3 days after PMSG treatment. At 0, 1, 2, 3, 4, and 5 days after PMSG treatment, sera were collected by cardiac puncture. The serum concentrations of progesterone (P(4)), testosterone (T), and estradiol-17 beta (E(2)) were determined by radioimmunoassay.
  
  
  RESULTS
  The serum concentrations of P(4) tended to be lower in both the pentobarbital- and the ketamine-treated groups compared with the control group. Significant differences were found on days 3 and 4 after pentobarbital and on days, 1, 4, and 5 after ketamine administration. Serum concentrations of T were also suppressed in both the pentobarbital and the ketamine-treated groups, whereas E(2) concentrations decreased only in the ketamine-treated group.
  
  
  CONCLUSIONS
  Pentobarbital and ketamine decrease serum sex hormone concentrations in PMSG-primed female rats.
authors.affiliation: Korea Atomic Energy Research Institute, Yusong PO Box 105, Taejon 305-600, Korea.
authors.forename: C J
authors.initials: CJ
authors.lastname: Lee
authors.forename: B R
authors.initials: BR
authors.lastname: Do
authors.forename: J K
authors.initials: JK
authors.lastname: Kim
authors.forename: Y D
authors.initials: YD
authors.lastname: Yoon