Figure 6.

Repetitive stimulation at the gamma frequency enhances GABA release. Stimulation trains (500 ms duration) at 40 Hz delivered to axons surrounding the somas of mature granule cells resulted in robust increases in GABA release in PGC-1α −/− mice. A, The amplitude of the last IPSC in the train (gray dotted lines) was significantly larger in −/− compared to +/+ animals. Reponses were normalized to the peak amplitude of the first IPSC (black dotted line). B, Total charge during the train (gray area) was also significantly increased in −/− compared to +/+ mice. Traces shown in A and B are the average normalized response from all 12 cells in +/+ and −/− mice. C, Asynchronous release was apparent in individual IPSCs during and after the 40 Hz train in recordings from −/− mice. Seven individual episodes from one cell in a +/+ and −/− mouse are overlaid.