Enhanced glutamate spillover in DTg mice. (A) STCs elicited by a single stimulus (black trace) and subtracted traces showing responses to the 5thstimulus (red trace). Insets: STCs are normalized and aligned so that the peaks are superimposed to facilitate comparison of decay. (B) τdecay of STC was not significantly different between WT and DTg mice. n (number of cells) = 16, N (number of animals) = 5 for WT, n = 14, N = 4 for DTg. (C) Frequency dependence of R1/5 decay in WT and DTg mice. n = 5, N = 1 for WT, n = 5, N = 2 for DTg. (D) Representative NMDA currents recorded from CA1 pyramidal neurons in response to a single stimulus (black trace) and trains of stimuli (5 stimuli, 100 Hz, red trace) at +40 mV. Traces induced by 5 stimuli are normalized to the peak amplitude induced by a single stimulus. (E) The ratio of total charge transfer by NMDA receptors (train/single EPSCNMDA area) induced by trains of stimuli to a single stimulus was increased in DTg mice. n = 8, N = 3 for WT, n = 8, N = 4 for DTg. *P < 0.05, unpaired t test. The values on the graphs represent mean ± SEM.