In vivo and in vitro alteration of nicotine metabolism by the major metabolite of phenytoin.
The influence of hydroxyphentoin (HPPH), the major metabolite of phenytoin, on the in vitro and in vivo metabolism of nicotine was examined. In rat liver 9,000 g supernatant HPPH decreased the appearance of cotinine from nicotine by 65% while not influencing the disappearance of nicotine or the appearance of nicotine-l'-N-oxide. In vivo, HPPH inhibited both nicotine elimination and cotinine formation but did not affect nicotin-l'-N-oxide formation.
In vivo and in vitro alteration of nicotine metabolism by the major metabolite of phenytoin. The influence of hydroxyphentoin (HPPH), the major metabolite of phenytoin, on the in vitro and in vivo metabolism of nicotine was examined. In rat liver 9,000 g supernatant HPPH decreased the appearance of cotinine from nicotine by 65% while not influencing the disappearance of nicotine or the appearance of nicotine-l'-N-oxide. In vivo, HPPH inhibited both nicotine elimination and cotinine formation but did not affect nicotin-l'-N-oxide formation.