[Effect of age and phenobarbital on liver activity of mixed function oxidase].

Effect of age and phenobarbital on the rat mixed function oxidase activity was studied. Male Wistar rats 0.5-, 1-, 2-, 4-, 8-, 12-, 20- and 28 month-old were used. In this study the levels of cytochrome P-450 and cytochrome b5. NADPH-cytochrome P-450 and NADH-cytochrome b5 reductases activity were examined. Both cytochrome P-450 and NADPH-cytochrome P-450 reductase activity was induced by phenobarbital in all animals. Maximum was observed in 4- and 8-month-old for hemoprotein and 2-month-old rats for reductase activity but minimum in youngest and oldest one respectively. On the contrary, cytochrome b5 and NADH-cytochrome b5 reductase activity was inhibited after phenobarbital injection. The highest depression of cytochrome b5 content was found in youngest, but the enzyme activity in oldest rats.