Effects of acetaldehyde and/or ethanol on neutral amino acid transport systems in microvillous brush border membrane vesicles prepared from human placenta.

At 20 mM of acetaldehyde, the activities of three transport systems of L-alanine distinguished by the differences in their cation dependence, namely 1) Na+-specific, 2) Li+-dependent, and 3) Na+-independent systems, were significantly reduced in a similar manner. Only the Li+-dependent system was selectively inhibited at toxic concentrations of acetaldehyde and ethanol.