Development of Liver Mitochondrial Aldehyde Dehydrogenase Activities in the Foetal and Neonatal Rat

Abstract

Changes in the activities of a number of enzymes in the mammalian liver during foetal and postnatal development appear to reflect the different physiological needs of the developing animal faced with environmental alteration (Greengard, 1971). A study of the developmental histories of a number of enzymes in the mammalian liver has resulted in the emergence of two important features. One is that the activities of most enzymes studied do not increase steadily over a prolonged period but increase within hours or days to the activity seen in the adult. Secondly, the emergence of new enzymes or the upsurge of enzymes present at low activities is not evenly distributed along the age axis but occurs in clusters. In rat liver three eventful periods have been discerned (Greengard, 1971). One occurs in late foetal life, another on the first day after birth and another in the third postnatal week.