A dose-related impairment of spatial learning by the NMDA receptor antagonist, 2-amino-5-phosphonovalerate (AP5)

This paper describes an experiment which further tested the hypothesis that activation of N-methyl-D-aspartate receptors plays an important role in the neural mechanisms underlying certain kinds of learning and memory. The results demonstrate that a selective N-methyl-D-aspartate receptor antagonist, D-2-amino-5-phosphonovalerate, causes a dose-related and correlated impairment of both spatial learning and hippocampal long term potentiation in vivo. No dose of D-2-amino-5-phosphonovalerate was found to block long term potentiation without affecting spatial learning. These data therefore support the proposed link between long term potentiation and certain kinds of learning, and the role of N-methyl-D-aspartate receptors in both processes.