Fig. 1. Concentration-dependent inhibition of lamotrigine on the 5-HT₃ receptor currents.

(A) Sample traces show currents activated by 3 µM 5-hydroxytryptamine (5-HT) application (open bar) and co-application of 3 µM 5-HT with 3, 30, 100 µM of lamotrigine (LTG, closed bar) for 5 sec. (B) Representative traces show currents induced by application of 1 mM dopamine (DA) alone (open bar) and co-application with various concentration of lamotrigine (closed bar) for 5 sec. (C~E) A concentration-dependent block of lamotrigine on the peak amplitude and rise slope of 5-HT₃ receptor currents induced by 3 µM 5-HT (n=8) and 1 mM DA (n=6). Data were normalized to the value of the peak current amplitudes and rise slope induced by 3 µM of 5-HT alone or 1 mM DA alone, which was taken as 1. Each data represents mean±S.E.M.