[Age and the effects of barbiturates on rat liver microsome oxidative enzymes].

It was shown in experiments on male white rats aged 1, 3, 6 and 25 months that the content of cytochrome P 450 and aminopyrindemethylase activity of liver microsomes decrease in old animals as compared with younger ones. No age-associated differences were revealed in old rats as compared with adult ones as regards all the parameters studied. During administration of barbiturates the induction of aminopyrindemethylase, the content of cytochromes P 450 and b5, microsomal protein and liver weight is pronounced to a far greater extent in one-month-old animals, it being decreased with age. Changes in the duration of narcotic-induced sleep (administration of barbiturates) set in earlier and are more pronounced in young animals than in adult or old ones.