Fig. (2).

The affinity of the memantine to the NMDA receptor. ←: Resting conditions: NMDA receptors with the physiological Mg²⁺ block. ↑: Increased background: Left side: low to moderate affinity antagonist memantine binding to the NMDA receptor, Right side: without memantine the NMDA receptor is getting activated after the binding of glycin and glutamate. ®: Synaptic activity: Left side: after depolarization, without the memantine, the NMDA receptor is activated by the glycin and glutamate, Right side: after the depolarization the NMDA receptor becomes activated by the binding of glycin and glutamate, the Mg²⁺ block ceases. :memantine, : glutamate, ○:Mg²⁺, ●: glycin.