(RS)-AMPA ((±)-AMPA) monohydrate, a potent and selective agonist of the excitatory neurotransmitter L-glutamic acid and a glutamate analogue, does not interact with the binding sites of kainic acid or NMDA receptors, highlighting its selectivity [1] [2].

(RS)-AMPA monohydrate (10-3-10-4 M) leads to depolarizations of cultured rat spinal and brainstem neurones. The depolarization by (RS)-AMPA monohydrate is clearly dose-dependent, although there is a great variability of effects between individual neurones. Application of (RS)-AMPA monohydrate at 10-5 M produces only small depolarizations (3-7 mV), whereas at 10-4 M, the amplitudes of the depolarizations ranged from 4 to 33 mV. (RS)-AMPA monohydrate also causes an increase of the discharge rate of spontaneously firing neurones or sometimes evoked a short burst of action potentials in silent cells. (RS)-AMPA monohydrate exerts its depolarizing effects by activating glutamate/quisqualate receptors without affecting NMDA receptors [1].