Dehydroaripiprazole (OPC-14857, DM-14857) is the active metabolite of aripiprazole, primarily metabolized by CYP3A4 and CYP2D6. It inhibits glutamate release from rat prefrontocortical nerve terminals by activating dopamine D2 and 5-HT1A receptors, reducing nerve terminal excitability and VDCC activation through a PKA-mediated signaling cascade, potentially contributing to its neuroprotective effects in excitotoxic injury.