Figure 3.

Effects of excitatory neuromodulators on respiratory rhythm generated by E18.5 Lbx1 mutant brainstem–spinal cord–diaphragm preparations. A, Examples of integrated, rectified diaphragm EMG recordings from the brainstem–spinal cord–diaphragm preparations of E18.5 Lbx1 mutant mice show excitatory actions of SubP 1(μm), TRH (1 μm), ampakine CX546 (200 μm), and noradrenaline (25 μm). B, Population data showing respiratory frequency relative to control after addition of each agent as well as 5-HT (25 μm). Each data point was from four to five preparations tested. *p < 0.05 relative to control.