Vesicular glutamate and GABA transporters sort to distinct sets of vesicles in a population of presynaptic terminals.
Vesicular glutamate transporters (VGLUTs) 1 and 2 are expressed by neurons generally accepted to release glutamate as a neurotransmitter, whereas VGLUT3 appears in populations usually associated with a different classical transmitter. We now demonstrate VGLUT2 as well as the vesicular GABA transporter (VGAT) in a subset of presynaptic terminals in the dentate gyrus of the rat hippocampal formation. The terminals are distributed in a characteristic band overlapping with the outer part of the granule cell layer and the inner zone of the molecular layer. Within the terminals, which make asymmetric as well as symmetric synapses onto the somatodendritic compartment of the dentate granule cells, the 2 transporters localize to distinct populations of synaptic vesicles. Moreover, the axons forming these terminals originate in the supramammillary nucleus (SuM). Our data reconcile previous apparently conflicting reports on the physiology of the dentate afferents from SuM and demonstrate that both glutamate and GABA may be released from a single nerve terminal.
Boulland
Jean-Luc
JL
The Biotechnology Centre of Oslo, Norway.
Jenstad
Monica
M
Boekel
Amber J
AJ
Wouterlood
Floris G
FG
Edwards
Robert H
RH
Storm-Mathisen
Jon
J
Chaudhry
Farrukh A
FA
D000818:Animals; D006624:Hippocampus / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D017729:Presynaptic Terminals / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013572:Synaptic Vesicles / Q000378:metabolism*; D014018:Tissue Distribution; D050599:Vesicular Glutamate Transport Protein 2 / Q000378:metabolism*; D050495:Vesicular Inhibitory Amino Acid Transport Proteins / Q000378:metabolism*
C493475:Slc17a6 protein, rat; D050599:Vesicular Glutamate Transport Protein 2; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; C493406:vesicular GABA transporter