COMPARISON OF THE EFFECTS OF DL-threo-β-BENZYLOXYASPARTATE ON THE GLUTAMATE RELEASE FROM SYNAPTOSOMES BEFORE AND AFTER EXPOSURE OF RATS TO ARTIFICIAL GRAVITY

摘要

The present study assesses the efficiency of a newly developed competitive non-transported inhibitor DL-threo-β-benzyloxyaspartate as modulator of L-[14{sup left}C]glutamate release from synaptosomes. The experiments were carried out with Wistar rats subjected to normal or altered gravity conditions. We have demonstrated that exposure to artificial gravity led to a change in membrane transporter affinity to DL-TBOA, the magnitude of IC{sub}50 decreases from 18±2μM to 11±2μM. The investigations of depolarization-evoked L-[14{sup left}C]glutamate release mediated by membrane glutamate transporters have found that application of 10μM DLTBOA exerted a slighter effect on control rats in comparison with gravity-loaded ones (decrease of L-[14{sup left}C]glutamate efflux for control and centrifuge-induced loaded rats was equal to 15.2±2.2% and 26.2±3.9%, respectively). These data lead to believe that centrifuge-induced hypergravity had complex effect on glutamatergic transmission differently affected the processes of glutamate release and reuptake.