Administration of benzpyrene and allylestrenol in fetal or neonatal periods of life: does it make difference in the microsomal activity?

Administration of allylestrenol or benzpyrene in fetal and neonatal periods of life make the rats susceptible to phenobarbiturate induction. Changes to controls could be observed in three of the enzyme activities tested (p-nitrophenol-hydroxylase, cytochrome P450 and aniline-hydroxylase), with a dominance of the p-nitrophenol-hydroxylase among them. There seemed to be no difference in the action of allylestrenol and benzpyrene, although treatment protocol in the neonatal period proved to be more effective.