Figure 1. The slice preparation and experimental methodology.

A, schematic depiction of the transverse slice preparation, illustrating bilateral preBötC and XII motor nuclei (XII), as well as the semicompact division of the nucleus ambiguous (scNA). Patch and suction electrodes are also illustrated. Recordings of the intracellular voltage trajectory of a preBötC neuron (V_M) and the integrated XII motor output are shown for three cycles of inspiratory activity. B, perforated-patch and whole-cell recordings. The perforated-patch configuration (PP; left panel) is confirmed by the failure of the Lucifer yellow in the patch-pipette solution to dialyse the neuron. The whole-cell configuration (WC; right panel) allows Lucifer yellow to fill the neuron. The voltage traces shown below verify that the underlying depolarization of the inspiratory burst, i.e. the inspiratory drive potential, can be accurately measured in PP mode as compared to the first minute of WC mode. Baseline membrane potential was –60 mV.