To which neurotransmitter(s) do AMPA and NMDA synapses respond?To which neurotransmitter(s) do AMPA and NMDA synapses respond?

- AMPA responds to acetylcholine, and NMDA responds to norepinephrine.
- AMPA responds to glutamate, and NMDA responds to GABA.
- Both respond to GABA.
- Both respond to glutamate.