Abstract
Aspartate and glutamate are the principal candidates for the excitatory neurotransmitter released by the lateral olfactory tract (LOT) in prepyriform cortex of the rat. Identity of action of the natural transmitter with exogenous glutamate and/or aspartate, however, has not yet been demonstrated. We show that bath-applied 2-amino-4-phosphonobutyric acid, a presumed specific glutamate antagonist, blocks LOT-stimulated prepyriform field potentials and single unit activity but not the single unit response to ionophoretically applied glutamate or aspartate in rat olfactory cortex slices. These results suggest that neither aspartate nor glutamate is the LOT transmitter. Responses to ionophoretically applied N-methyl-DL-aspartate, kainic acid, and DL-homocysteate were clearly decreased by 2-amino-4-phosphono-butyric acid. This suggests that these agents, usually presumed to be aspartate or glutamate agonists, act at different receptors than aspartate and glutamate.
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Supported by Armed Forces Radiobiology Research Institute, Defense Nuclear Agency, under Research Work Unit MJ 60203. The views presented in this paper are those of the authors. No endorsement by the Defense Nuclear Agency has been given or should be inferred.
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Hori, N., Auker, C.R., Braitman, D.J. et al. Lateral olfactory tract transmitter: Glutamate, aspartate, or neither?. Cell Mol Neurobiol 1, 115–120 (1981). https://doi.org/10.1007/BF00736043
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DOI: https://doi.org/10.1007/BF00736043