Memantine

Question 1

what is Memantine

Answer 1

A NMDA receptor antagonist, an amantadine derivative

Question 2

what is Memantine used to treat?

Answer 2

Dementia

Question 3

mode of action of Memantine?

Answer 3

binds to the NMDA receptor-operated cation channels

Question 4

how does Neuronal degeneration occur?

Answer 4

Prolonged increased levels of glutamate in the brain of demented patients counter the voltage-dependent block of NMDA receptors by Mg2+ ions and allow a continuous influx of Ca2+ ions into cells,

Question 5

how does memantine protect again chronically elevated concentrations of glutamate?

Answer 5

Memantine binds more effectively than Mg2+ ions at the NMDA receptor,
effectively blocking the prolonged influx of Ca2+ ions through the NMDA channel whilst preserving the transient physiological activation of the channels by higher concentrations of synaptically released glutamate

Question 6

where else does memantine have antagonistic activity, and what is the potency at that receptor?

Answer 6

Memantine also has antagonistic activity at the type 3 serotonergic (5-HT3) receptor with a potency that is similar to that at the NMDA receptor,

Question 7

where does memantine have lower antagonistic activity?

Answer 7

at the nicotinic acetylcholine receptor.