Copper metabolism in pregnant and pospartum rat and pups.

Abstract

A detailed study was made of Cu metabolism in rats during and after pregnancy and in the fetuses and pups up to the age of 6 wk. Maternal ceruloplasmin levels increase only briefly at the beginning of the last week of pregnancy. They then decrease to normal levels at term and decrease markedly in the early postpartum period. Biliary excretion of Cu and 67Cu almost stops at term and remains decreased for 2 wk. In spite of this, there is no increase in hepatic Cu levels. Except for a 1-2 day period shortly after delivery, maternal rats have a positive Cu balance if lacteal elimination of Cu is ignored. Levels of Cu in milk drop at about the 4th day postpartum. Fetal hepatic Cu levels are already above adult levels, but the concentration almost doubles during the first wk after birth; it decreases to adult levels by 6 wk of age. Ceruloplasmin levels, which are very low in the pups at birth, increase sharply in the first 24 h and quickly achieve adult levels. Large quantitative differences also occur between the pups and adults in concentrations of Cu in the brain and kidney. Qualitative differences, measured with 67Cu, are most notable when the neonatal liver is compared with the adult liver.