glutamate receptors

Glutamate is a neurotransmitter in nerve cells which binds to all glutamate receptors located on neuron membranes, and is an example of a transmembrane receptor.
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Glutamate receptors are protein molecules that helps gate the flow of ions across a nerve cell's membrane. They play a role in the formation of new connections between nerve cells (and so, in learning and memory). The receptors are normally activated by aspartate and glutamate. In amnesic shellfish poisoning, domoic acid acts as an excitotoxin that very strongly activates some of these receptors, preventing their proper functioning.