Effect of storage of biological material on the activity of biotransformation enzymes

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Jana Jelínková Consultant: Doc. Ing. Barbora Szotáková, Ph.D. Title: Effect of storage of biological material on activity of biotransformation enzymes Effect of storage of liver and subcellullar fractions on the activities of biotransformation enzymes was studied. Activities of oxidation enzymes - cytochromes P450 (CYP1A, 2B, 2C, 3A) and flavin-containg monooxygenases (FMO), carbonyl-reducing enzymes (AKR1A1, AKR1C, 11β-HSD,CBR) and conjugation enzymes (UGT, GST) were observed. Microsomal and cytosolic subcellular fractions prepared from differently stored liver of sheep (Ovis aries) were used. (A) from fresh tissue frozen in the liquid nitrogen. (B) from liver that was stored at -80C, the temperature gradually increased to 0C and then gradually decreased back to -80C. The half of prepared microsomal and cytosolic subcellular fractions from liver stored in liquid nitrogen (A) was processed by the same storage procedure as liver (B). The second half was stored at -80C. Activities of tested biotransformation enzymes were determined toward their relatively specific substrates. The subcellular fractions were also incubated with xenobiotics (oracin, flubendazole and albendazole) and the..