Impact of neonatal benzpyrene imprinting on liver microsomal enzyme induction by benzpyrene and phenobarbital in adulthood.

A single neonatal treatment of rats with benzpyrene accounted for a durable induction of the liver microsomal enzyme (PSMO) system. Neonatal treatment with benzpyrene enhanced the inducing action of phenobarbital administrated in adulthood, but did not change the effect of benzpyrene treatment in the adult age. It follows that the imprinting and inducing effects of the neonatal benzpyrene treatment took different trends.