Fig. 7.
The duration of the field bursts in the dentate gyrus is altered by local pH acidification. A, Three extracellular electrodes (1–3) were placed 300 μm apart along the dorsal aspect of the dentate gyrus. B,Top, Spontaneous field bursts were highly synchronized in the whole dentate gyrus. Inset, A faster timescale shows that the onset of field bursts at the three recording sites had a small delay but that the termination of bursts at these sites was completely synchronized. Middle, This set of chart recordings shows that local application of acidic medium near the middle electrode blocked the field burst at that location and disrupted the synchronization between sites 1 and 3. Bottom, The effect of local acidic medium was reversible. C, When acidic medium was locally applied after the onset of one field burst (*), it blocked that field burst quickly. D, If the acidic medium was applied before the onset of one field burst (*), it delayed the onset and stopped it early.