Fig. 7.

ATPD induction in LS neurons is dependent on DHPG concentration and mediated by group I mGluRs. A, representative traces showing blockage of ATPD induction by 30 µM YM298198 plus 10 µM MPEP ejected together with 30 µM DHPG to an LS neuron in all three current clamp conditions. Arrows indicate the time of drug ejection (5–20 psi, 30 ms). Scale bars: 3 s, 10 mV for CC-70; 0.5 s, 10 mV for CC-45, 50 ms, 10 mV for CC-80s. B, Quantification based on area under the trace for the sweep with the largest depolarization at CC-80s. Shown are means±SEM for DHPG-evoked depolarization in the absence (n =75) or presence of YM298198 and MPEP (n =6). **P <0.01, compared to DHPG alone. C, Stacked bar graph showing proportions of LS neurons that showed BTD and ATPD in response to the CC-80s protocol at different DHPG concentrations. The remaining neurons did not respond to the stimulation. D, Concentration–response curve of DHPG-induced membrane depolarization at CC-80s. Quantification was as in B; n =7, 6, 5, 75, and 7 for 1, 5, 10, 30, and 200 µM DHPG, respectively. For 30 µM DHPG, the same data as in B are shown