Used primarily in neuroscience research as a selective NMDA receptor antagonist. It helps block the action of glutamate, a major excitatory neurotransmitter, at NMDA receptors by competitive inhibition, making it a valuable tool for studying synaptic plasticity, including long-term potentiation (LTP) and long-term depression (LTD), learning, and memory processes.

Commonly applied in in vitro and in vivo experiments to investigate the role of NMDA receptors in neuronal signaling and neurodegenerative conditions such as Alzheimer's disease, Parkinson's disease, and hypoxia-induced brain damage, where NMDA receptor dysregulation contributes to neuronal degeneration. DL-AP5 enables researchers to model or inhibit these pathological processes and test potential therapeutic strategies to prevent or slow neural decline.

Also used to induce long-term depression (LTD) in electrophysiological studies.