Figure 7.
Effect of gamma frequency stimulation on evoked GABAA receptor-mediated currents during development. a and b, Inward currents elicited by gamma frequency (50 Hz) train stimulation of neuronal fibers in two NG2 cells held at −70 mV at PN11 (a) and PN25 (b) in the presence of 10 μm NBQX and 50 μm d-AP-5. Both currents were normalized at the first stimulation pulse. Traces in SR95531 were subtracted to the trace control (average of five traces in each case); artifacts were blanked. The current peaks reached at the first three stimulation pulses for the cell at PN25 are indicated (arrows). Note the presence of single synaptic events within the train in the second PN week and the larger temporal summation of spillover-mediated currents in the fourth PN week.