[Induced modification of liver NADPH-cytochrome P-450 activity and II microsomal electron transport chain as a function of age in rats]

In this paper we showed age effect on NADPH-cytochrome P-450 reductase activity, cytochrome b5 and NADH-cytochrome b5 reductase from rat liver. We discussed effect of some I, II and III classes inductor also. Activity NADPH-cytochrome P-450 reductase softly decreased from 0.5-2-month of life, but in older groups gradually increased. In 28-month-old rats it was twice fold youngest. Phenobarbital and dexamethasone (without 28-month-old age rats) induced but beta-naphthoflavone inhibited activity of this reductase. Cytochrome b5 content softly decreased to 4-month of life. In older animals changed of this hemoprotein content were not observed. The examined inductors of monooxygenase system decreased cytochrome b5 level. NADH-cytochrome b5 reductase activity increased to 1-month of life, but in older group decreased. After 2-month changes of activity were very small only. Phenobarbital, beta-naphthoflavone and dexamethasone inhibited activity of this reductase.