Physiological Properties of Supragranular Cortical Inhibitory Interneurons Expressing Retrograde Persistent Firing

Figure 3

Persistent firing layer 2/3 interneurons showed specific intrinsic electrical properties. (a) The pie chart on the left shows the percentage and number (in braket) of fast-spiking (FS) and non-fast-spiking (nFS) cells of the entire population of recorded layer 2/3 interneurons. The pie chart on the right further subdivides the percentage and number of neurons which express or do not express persistent firing in either fast-spiking or non-fast-spiking interneurons (FS-PF, FS-nPF, nFS-PF, and nFS-nPF) (right). The one and only fast-spiking persistent firing neuron (FS-PF) was not further analysed. The diagrams show (b) Δvoltage (mV difference between resting Vm and spike threshold) and (c) input resistance in the different interneuronal groups (FS nonpersistent firing, FS-nPF; nFS nonpersistent firing, nFS-nPF; nFS persistent firing, nFS-PF). The dots represent single neurons and the horizontal black lines represent the mean of each group. (d) Firing rate versus current injection curve for the three identified interneuronal classes. (e) Magnification of the rectangle dashed area in (d) to emphasize the difference between nFS-nPF and nFS-PF interneurons. Here the curve for FS-nPF was omitted for clarity.

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