Modulatory Effects of Memantine on Neuronal Response Properties in Rat Barrel Cortex.

Introduction: Memantine as N-Methyl-D-Aspartic Acid (NMDA) receptor antagonist is used in some neurological disorders. Moreover, memantine presents modulatory effects on the somatosensory information processing in healthy subjects. This study investigated the effects of memantine on electrophysiological properties of barrel cortex neurons in male rats.

Methods: Single unit recording was used to evaluate the electrophysiological properties of barrel cortex neurons. The neural responses to the Principal Whisker (PW), Adjacent Whisker (AW), and combined displacement of two whiskers [20 ms Inter-Stimulus Intervals (ISIs)] were recorded before and 2 hours after memantine gavage (10 mg/kg). A Condition Test Ratio (CTR) was calculated for assessing inhibitory interactions.

Results: Two hours after memantine gavage, neuronal ON and OFF responses to PW deflection were decreased. Furthermore, CTR for both ON and OFF responses was decreased following memantine administration.

Conclusion: The current study demonstrated that memantine modified neural response properties in the rat barrel cortex.

Highlights: Memantine modulated excitatory receptive fields in the rat somatosensory cortex.Memantine decreased integrative receptive fields in rat somatosensory cortex.

Plain Language Summary: As an NMDA receptor antagonist, memantine is used to treat moderate to severe Alzheimer's disease. Memantine has beneficial effects on cognition, mood, and perform daily activities. However, the current study results suggested that memantine may affect information processing in the somatosensory system. This should be considered for future research in the clinic.