The Usefulness of Saliva as a Biological Material for the Determination of Pharmacokinetics of Model Drugs (Antipyrine, Caffeine, Paracetamol) in Calves: Comparative Study

摘要

The aim of this study was to evaluate usefulness of saliva as a biological material for determination of pharmacokinetics of model drugs (antipyrine, caffeine and paracetamol) in calves at different age. For the experiment, 30 Black and White calves (BW) at the age of 10 and 40 days were divided into three groups. The calves of group I received antipyrine (10 mg kg-1 bw.), group II caffeine (5 mg kg-1 bw.) and group III paracetamol (10 mg kg-1 bw.). Samples of blood and saliva were collected from all examined animals. The concentration of antipyrine and paracetamol was measured spectrophotometrically. The concentration of caffeine was evaluated by EMIT method. The pharmacokinetics of antipyrine were estimated using one-compartment model whereas the pharmacokinetics of caffeine and paracetamol using non-compartment model. The following pharmacokinetic parameters were evaluated: volume of distribution, relative volume of distribution, mean residence time; biological half-life, metabolic clearance, relative metabolic clearance and level of model drugs-plasma proteins fractions. Results obtained in the experiment (not statistically significant differences in pharmacokinetic parameter values of antipyrine and caffeine and statistically significant according to paracetamol) determined on the basis of model drugs concentration in blood and saliva showed that saliva has potential to be used as a biological material from calves but only for evaluation of pharmacokinetics of antipyrine and caffeine. However, it cannot be used for assessment of pharmacokinetics of paracetamol.