Is glutamic acid the pyramidal tract neurotransmitter?

Area of Science:

• Neuroscience
• Neuropharmacology

Background:

• The cuneate nucleus processes sensory information.
• The role of neurotransmitters in the cuneate nucleus is under investigation.

Purpose of the Study:

• To investigate the role of glutamate as a neurotransmitter in the rat cuneate nucleus.
• To examine the effects of 1-hydroxy-3-amino-pyrrolidone-2 (HA-966) on neuronal excitation.

Main Methods:

• Neuronal excitation was studied in the rat cuneate nucleus.
• 1-hydroxy-3-amino-pyrrolidone-2 (HA-966) was applied via microiontophoresis.
• Neuronal responses to glutamic acid, acetylcholine, and pyramidal tract stimulation were recorded.

Main Results:

• 1-hydroxy-3-amino-pyrrolidone-2 (HA-966) antagonized excitation by glutamic acid but not acetylcholine.
• HA-966 blocked short-latency excitation in 70% of cuneate neurons following pyramidal tract stimulation.

Conclusions:

• Glutamate or a related amino acid is likely the neurotransmitter released by pyramidal tract neurons.
• HA-966 is a useful tool for studying glutamate's role in the central nervous system.