Journal archive > 2005 > N3, May-June

Modulating effect of glutamate transport inhibitors on accumulation
and release of the neuromediator by rat brain nerve terminals

T. A. Borisova, N. V. Krisanova, N. H. Himmelreich

L-[14C]glutamate uptake and release processes in nerve terminals has been investigated using the nontransportable and transportable competitive inhibitors of glutamate transport as tools. The effects of DL-threo-?-benzyloxyaspartate (DL-TBOA) and DL-threo-?-hydroxyaspartate (DL-THA) on the accumulation of L-[14C]glutamate have been evaluated after the exposure of rats to centrifuge-induced hypergravity. Both analogs potently inhibited the L-[14C]glutamate uptake in a dose-dependent manner (100 ?M glutamate, 30 s incubation period). The IC50 values for DL-TBOA calculated on the basis of curves of non-linear regression kinetic analysis was 18 ± 2 ?M and 11 ± 2 ?M (? 0.05) before and after the exposure to artificial gravity, respectively. L-THA, transportable analog, exhibited similar inhibitory characteristics (18 ± 2 and 12 ± 2 ?M, respectively). We have also demonstrated that DL-TBOA exerted slighter effect on depolarization-evoked carrier-mediated L-[14C]glutamate release in control rats in comparison with gravity-loaded ones. Thus, DL-TBOA had complex effect on glutamatergic transmission, inhibited uptake and release of L-glutamate, and perhaps, became more potent under centrifuge-induced hypergravity.

Recieved: 2005-02-12

Published at the site: 2005-05-05

The original article in Russian is available for download in PDF format.


© The Ukrainian Biochemical Journal