P.1.c.010 Gender-dependent influence of bupropion pretreatment on locomotor activity and the activity of hepatic CYP2D2 in rats

One of the most important enzymatic systems participating in drug metabolism is cytochrome P450 (CYP450). CYP450 consists of many isoforms which activity of is influenced by numerous endogenous (e.g. gender, pathophysiological status, age) and exogenous factors (e.g. xenobiotical inhibitors and inducers). Although bupropion is not metabolized by CYP 2D6 (human ortologue of rat CYP2D2), there is certain potential for interaction when bupropion is co-administered with other drugs metabolized by this isoenzyme, too. The aim of the present study was to determine the influence of gender and administration of bupropion on the CYP450 isoform 2D2 (CYP2D2) activity. As selective markers of the metabolic activity of CYP2D2 dextromethorphan (DEM) and its metabolite dextrorphane (DOR) were used. In animals treated with bupropion compared to control animals administered with saline the inhibitory effect of bupropion was expressed as a decrease of DOR in the 30th, 60th and 120th minutes of perfusion. The influence of gender on locomotor activity has shown that activity in intact females were similar as in the intact males. In the bupropion treated animals females were significantly more active in subsequent open field tests then in males.