Which type of glutamate receptor is known to be the faster of the two main types?

The AMPA receptor is recognized for its rapid response to glutamate, making it the faster of the two primary types of glutamate receptors. When glutamate binds to AMPA receptors, they mediate fast excitatory synaptic transmissions in the central nervous system. This results in a quick influx of sodium ions into the neuron, leading to a rapid depolarization of the postsynaptic membrane.

In contrast, NMDAR (N-Methyl-D-Aspartate receptor) activation is slower because it involves a voltage-dependent mechanism and requires both binding of glutamate and a change in membrane potential to remove a magnesium ion that blocks the channel. Kainate receptors also transmit signals more quickly than NMDARs but typically not as fast as AMPA receptors. Metabotropic receptors, on the other hand, are coupled with intracellular signaling pathways and modulate neuronal excitability over a longer timescale, further confirming the swift nature of AMPA receptors in neuronal communication.