Fig. 5.
NT-mediated enhancement of glutamate release is related to the presynaptic Ca2+ influx via L-type Ca2+ channels and requires the function of calmodulin. A, Application of BAPTA-AM (200 μM) by itself decreased AMPA EPSCs and blocked NT-induced augmentation of AMPA EPSCs. B, Intracellular perfusion of BAPTA (10 mM) via the recording pipettes failed to alter significantly NT-mediated augmentation of AMPA EPSCs. C, Pretreatment of slices with and continuous bath application of thapsigargin (10 μM) failed to change NT-induced enhancement of AMPA EPSCs significantly. D, Pretreatment of slices with and continuous bath application of nimodipine (10 μM) blocked NT-induced increases in AMPA EPSCs. E, Pretreatment of slices with and continuous bath application of verapamil (10 μM) blocked NT-induced increases in AMPA EPSCs. F, Application of W7 (50 μM), the calmodulin inhibitor, in the same fashion blocked NT-induced increases in AMPA EPSCs.