A PRELIMINARY EVALUATION OF DRUG BIOTRANSFORMATION IN HEPATOCYTES OF GENETICALLY DEFINED RAT STRAINS

This study was directed to use the genetically developed isoprenaline- sensitive (S), isoprenaline-resistant (R) and spontaneous hypertensive rats (SHR) as standard diseased animal models for in vitro liver func tion evaluation of drug biotransformation. Hepatic hexobarbital hydrox ylase and glutathione transferase (GST) were evaluated by using hexoba rbital and 1-chloro-2,4-dinitrobenzene (CDNB) as substrates, at concen trations of 0.21 mmol/l and 1 mmol/l, respectively. The assay was cond ucted by using isolated hepatocytes in suspension and hepatocytes in a bioreactor configuration. The data demonstrate that there are certain cellular pharmacokinetic differences in hexobarbital hydroxylase and GST activities in hepatocytes obtained from Wistar, SHR, R and S strai ns which can be better demonstrated, when using the model of perfused and immobilized hepatocytes.