[Tracer kinetic studies on maternal-fetal amino acid transport in Wistar rats].
The experiments were designed to determine the amount of free amino acids which passes through the placenta from the maternal pool in plasma to the fetus. On day 19 of gestation we determined the growth rate of the rat fetus to be about 39 microgram amino nitrogen/minute/litter. Uniformly labelled [14 C]-L-leucine was used in our experiments. The specific radioactivity was measured in the maternal plasma amino acids and in fetal amino acids and proteins from zero to sixty minutes after pulse labelling. By means of compartmental analysis we calculated the transfer rate of amino nitrogen from the mother to the fetus to be 89 microgram/min/litter. The rate of amino nitrogen acccumulation in fetal carcass proteins was 39 microgram amino nitrogen/min/litter. The importance of our results in fetal metabolism is discussed.
D000818:Animals; D005260:Female; D005333:Fetus; D007700:Kinetics; D007930:Leucine / Q000097:blood / Q000378:metabolism*; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D051381:Rats
D007930:Leucine
Tracerkinetische Untersuchungen zum materno-fetalen Aminosäure-transport bei Wistarratten.