Lamotrigine inhibition of glutamate release from isolated cerebrocortical nerve terminals (synaptosomes) by suppression of voltage-activated calcium channel activity

Lamotrigine (LAG) is an antiepileptic drug which is believed to suppress se izures by inhibiting the release of excitatory neurotransmitters. The prese nt study was aimed at investigating the effect of LAG on the 4-aminopyridin e (4AP)-evoked glutamate release in cerebrocortical nerve terminals (synapt osomes). LAG inhibited the release of glutamate evoked by 4AP in a concentr ation-dependent manner. This inhibitory effect was associated with a reduct ion in the depolarization-evoked increase in the cytoplasmic free Ca2+ conc entration ([Ca2+]c).