title: Sex-related differences in disposition and response to phenprocoumon in rats.
abstract: The pharmacokinetics and the pharmacological response to phenprocoumon have been studied in female and male inbred Lewis-Wistar rats. A significantly lower clearance was found in female than in male rats (7.9 +/- 1.4 vs 24.5 +/- 2.5 mL h-1 kg-1, respectively; t = 15.09, P less than 0.001) as well as a lower apparent volume of distribution (288 +/- 46 vs 617 +/- 105 mL kg-1; t = 7.58, P less than 0.001) and a longer half-life (25.5 +/- 3.4 vs 17.5 +/- 1.8 h; t = 5.16, P less than 0.001). The binding of phenprocoumon was higher in female than in male rats (fu: 0.0096 +/ 0.0008 vs 0.0124 +/- 0.0007, respectively; t = 6.66, P less than 0.001). The total (C) as well as the unbound concentration (Cu) needed to elicit a 50% decrease in the prothrombin complex synthesis rate was substantially higher in female rats: C50 was 377 +/- 98 ng mL-1 in female and 155 +/- 29 ng mL-1 in male rats (t = 5.32, P less than 0.001), whereas Cu50 was 3.6 +/- 0.7 ng mL-1 in female and 1.9 +/- 0.3 ng mL-1 in male rats (t = 5.50, P less than 0.001). However, because of the lower clearance and volume of distribution and the longer half-life in female rats, the female rats experienced a higher cumulative effect than male rats to 0.34 mg kg-1 i.v. doses.
mesh_terms: D015110:4-Hydroxycoumarins / Q000493:pharmacokinetics*; D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D005260:Female; D008297:Male; D010644:Phenprocoumon / Q000493:pharmacokinetics* / Q000494:pharmacology; D011485:Protein Binding; D011516:Prothrombin / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012737:Sex Factors
chemical_list: D015110:4-Hydroxycoumarins; D001798:Blood Proteins; D011516:Prothrombin; D010644:Phenprocoumon