Abstract
The study focused on the release of glutamate by reversal of Na + -dependent glutamate transporters that was investigated in cortical synaptosomes isolated from Wistar rats subjected to centrifuge-induced hypergravity of 10×g for 1 h. Transportable competitive inhibitor of glutamate transporters—DL-threo-beta-hydroxyaspartate (DL-THA) induced the release of L-[14C]glutamate via heteroexchange that consisted of 22.5 ± 1.7% of total label in normal gravity and 23.7 ± 1.7% in altered gravity conditions. Inhibition of the ability of synaptic vesicles to accumulate the neuromediator by preliminary treatment of synaptosomes with the protonophore (FCCP) augmented the release of cytosolic L-[14C]glutamate evoked by DL-THA from 44.0 ± 2.0% to 52.0 ± 2.3% of total label for G-loaded animals as compared to controls. Thus, combined application of DL-THA and FCCP revealed the increase in transporter-mediated release of glutamate that might be evidence for hypoxic injury of neurons.
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Borisova, T., Krisanova, N. Presynaptic Release of Glutamate by Heteroexchange Under Altered Gravity Conditions. Microgravity Sci. Technol 21, 197–201 (2009). https://doi.org/10.1007/s12217-008-9049-9
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DOI: https://doi.org/10.1007/s12217-008-9049-9