title: Gender differences in ondansetron pharmacokinetics in rats.
abstract: It has been reported that ondansetron is primarily metabolized via hepatic CYP2D and 3A1/2 in male Sprague-Dawley rats, and CYP2D1 and 3A2 are male dominant and male specific isozymes, respectively, in rats. Thus, it could be expected that the pharmacokinetics of ondansetron would be changed in male rats compared with those in female rats. Thus, gender-different ondansetron pharmacokinetics were evaluated after its intravenous or oral administration at a dose of 8 mg/kg to male and female Sprague-Dawley rats. After intravenous administration of ondansetron to male rats, the AUC and time-averaged non-renal clearance (Clnr) of the drug were significantly smaller (22.6% decrease) and faster (27.3% increase), respectively, than those in female rats. This probably could be due to faster hepatic blood flow rate in male rats. After oral administration of ondansetron to male rats, the AUC of the drug was also significantly smaller (58.8% decrease) than that in female rats, and this could have been due mainly to increased intestinal metabolism of ondansetron in addition to increased hepatic metabolism of the drug in male rats.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea.
authors.forename: Si H
authors.initials: SH
authors.lastname: Yang
authors.forename: Kyung H
authors.initials: KH
authors.lastname: Yang
authors.forename: Myung G
authors.initials: MG
authors.lastname: Lee
mesh_terms: D000284:Administration, Oral; D000429:Alcohol Oxidoreductases / Q000378:metabolism; D000818:Animals; D019540:Area Under Curve; D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism; D051544:Cytochrome P-450 CYP3A; D000072467:Cytochrome P450 Family 2; D005260:Female; D007262:Infusions, Intravenous; D007413:Intestinal Mucosa / Q000378:metabolism*; D008099:Liver / Q000098:blood supply / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D017294:Ondansetron / Q000493:pharmacokinetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012702:Serotonin Antagonists / Q000493:pharmacokinetics*; D012737:Sex Factors
chemical_list: D008565:Membrane Proteins; D012702:Serotonin Antagonists; D017294:Ondansetron; D000429:Alcohol Oxidoreductases; D001189:Aryl Hydrocarbon Hydroxylases; C504568:Cyp2d1 protein, rat; C465260:Cyp3a2 protein, rat; C465138:Cyp3a23-3a1 protein, rat; D051544:Cytochrome P-450 CYP3A; D000072467:Cytochrome P450 Family 2