Effects of long-term smoking on the activity and mRNA expression of CYP isozymes in rats.

Background: To investigate the effect of long-term smoking on the activity and mRNA expression of cytochrome P450 (CYP) enzymes.

Methods: Sprague-Dawley rats were exposed to passive smoking 6 cigarettes per day for 180 days. A cocktail solution which contained phenacetin (20 mg/kg), tolbutamide (5 mg/kg), chlorzoxazone (20 mg/kg) and midazolam (10 mg/kg) was given orally to rats.

Pharmacokinetics and tissue distribution of clevidipine and its metabolite in dogs and rats.

The purpose of the current study was to examine the pharmacokinetic profiles and tissue distribution of clevidipine, an ultra-short-acting calcium antagonist in Beagle dogs and Sprague-Dawley rats, respectively. The pharmacokinetics and biodistribution of its primary metabolite H152/81 were also evaluated. Dogs received intravenous infusion of clevidipine at a dose rate of 17 μg/(kg·min), and rats were given intravenous administration of clevidipine at a dose of 5 mg/kg.

Development of a liquid chromatography-tandem mass spectrometry method for determination of butoconazole nitrate in human plasma and its application to a pharmacokinetic study.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of butoconazole in human plasma. Human plasma samples of 0.2 μL were pretreated by a single step protein precipitation procedure and analyzed using a high performance liquid chromatography (HPLC) electrospray tandem mass spectrometer system.