GRIN1
GRIN1 NMDA receptor — the molecular target that 1 compounds in the wiki act on.
In one line: A learning-and-memory receptor that ketamine blocks — with a rapid antidepressant effect.
GRIN1 is part of the NMDA receptor, central to learning and memory. Ketamine blocks it, which paradoxically triggers a surge of brain growth signals (BDNF) and rapidly regrows lost connections — lifting severe depression within hours instead of the weeks antidepressants take.
That's why a form of ketamine is now an approved treatment for depression that hasn't responded to other drugs. It's given under supervision because blocking this receptor also causes a dissociative, dream-like state.