C. Frahm et al., Presence of gamma-aminobutyric acid transporter mRNA in interneurons and principal cells of rat hippocampus, NEUROSCI L, 288(3), 2000, pp. 175-178
After release, neurotransmitters are removed from the extracellular space b
y high-affinity uptake. Specific sodium-dependent transporters serve this f
unction for the inhibitory transmitter gamma-aminobutyric acid (GABA). Howe
ver, it is largely unknown to which proportion GABA is taken up by GABAergi
c interneurons, glia cells or principal neurons. We analyzed the distributi
on of mRNA for the main GABA-transporter subtype in the hippocampus, GAT-1,
in adult rats. Most interneurons were strongly stained for GAT-1 mRNA, ind
icating re-uptake by the GABA-releasing cells. Surprisingly, prominent sign
als for GAT-1 were also found throughout the principal cell layers (granule
and pyramidal cells). These data indicate that GABA transporters may be pr
esent in non-GABAergic projection cells of the rat hippocampus which contri
bute to the clearance of GABA from the extracellular space. (C) 2000 Elsevi
er Science Ireland Ltd. All rights reserved.