[The changes in EPH gestosis placental amino acid transport activity (using human placental microvillous membrane vesicles)].

To elucidate the change in EPH gestosis placental amino acid transport activity, we investigated the uptake of L-alanine into microvillous membrane vesicles prepared from EPH gestosis placenta and from normal placenta by using a rapid filtration technique. 1. Alkaline phosphatase (ALP) was the marker enzyme of microvillous membrane vesicles (MMV). The ALP activity of mild EPH gestosis placental MMV didn't differ from that of normal placental MMV. On the other hand, the ALP activity of severe EPH gestosis placental MMV decreased compared to that of normal placental MMV. 2. The uptake of L-alanine into human placental MMV was dependent on the Na+ electrochemical gradient, so the transport across human placental MMV was a secondarily active one. The L-alanine transport activity of mild EPH gestosis placental MMV didn't differ from that of normal placental MMV. On the other hand, the L-alanine transport activity of severe EPH gestosis placental MMV decreased prominently compared to that of normal placental MMV.