The ontogeny of L-alpha-hydroxyacid oxidase isozymes in the mouse.

Mouse liver hydroxyacid oxidase isozymes are present at low levels at birth and increase in activity until day 13 after which HAOX-B almost disappears and HZOS-A is reduced to approximately one half the maximum level in the adultkidney. HAOX-G appears near day 13 post partum and increases until adult levels are reached, the female having four times the activity of the male. The pregnant female has significantly lower levels of HAOX-A and HAOX-B in the liver and higher activity of HAOX-B in the kidney. Developmental changes occur in the extent of epigenetic modification of mouse liver HAOX-A during the early neonatal period.