the uptake of alanine and phenylalanine on the fetal side was inhibited by both short-chain ( alanine , serine , cysteine ) and long-chain ( phenylalanine , methionine , leucine ) neutral amino acids . d-alanine had no effect on l-alanine uptake whereas d-phenylalanine significantly inhibited that of l-phenylalanine .
C0036720
serine
C0301715
neutral amino acids