The influence of age on the distribution of morphine and morphine‐3‐glucuronide across the blood–brain barrier in sheep

Abstract

The morphine K(p,uu) was above unity, indicating active transport into the brain; influx was significantly higher in premature lambs than in adult sheep. These results in sheep differ from those in humans, rats, mice and pigs where a net efflux of morphine from the brain is observed.