Figure 7. The I_CAN antagonist, flufenamic acid (FFA), attenuates inspiratory drive potentials.

A, 100 μm FFA reduces drive potentials but not the magnitude or frequency of XII motor discharge. The letters ‘a’ and ‘b’ indicate inspiratory bursts that are shown at high resolution in the inset (at right) for control (a) and 100 μm FFA (b). B, 300 μm FFA blocks inspiratory activity in 7 of 10 slices after 12 or more minutes of drug exposure. C, in the 3 remaining slices, 350 μm FFA blocks the respiratory rhythm, which does not restart in the presence of 1 μm substance P (SP), but does recover after > 1 h of washout. Baseline membrane potential was −60 mV for V_M traces in A (inset) and B. A (inset), B and C all have separate time calibrations.