An NMDA receptor antagonist (Ki = 40 nM in a radioligand binding assay); selectively selectively inhibits glycine- over kainate-induced NDMA currents at 15 μM in Xenopus oocytes expressing rat NMDA receptors; reduces NMDA-induced neurotoxicity in primary rat cortical neurons from 1 to 10 μM; reverses mechanical hyperalgesia in magnesium-deficient rats in a dose-dependent manner from 0.97-97 nmol; blocks the positive ionotropic effect, hypertension, and increase in myocardial oxygen demand induced by electrical stimulation of the PVN in anesthetized rabbits; increases social interaction time and time spent in the open arms of the elevated plus maze; disinhibits conflict responding in the Cook and Davidson conditioned conflict paradigm