Figure 1.

Stimulation of DRN with acidosis-induced arousal from sleep in Lmx1b^f/f but not Lmx1b^f/f/p mice. A, Sagittal schematic view of mouse brain demonstrating cannula placement into DRN (green). Medullary raphe depicted in purple for reference. B, EEG and EMG traces depicting lack of arousal from sleep with perfusion of normal aCSF into DRN (left) and arousal from sleep with perfusion of acidified aCSF into DRN (right) in an Lmx1b^f/f mouse. Calibration: vertical, 20 μV; horizontal, 20 s. C, EEG and EMG traces depicting lack of arousal from sleep with perfusion of normal (left) or acidified (right) aCSF into DRN of an Lmx1b^f/f/p mouse. Calibration as in B. D, Mean arousal latencies for Lmx1b^f/f (black) and Lmx1b^f/f/p (red) mice treated with normal (control; solid bars) or acidified (acidosis; open bars) aCSF. Data are mean ± SEM. n = 10 per group. *p < 0.001. E, Percentage change in time spent in Wake (left) and NREM (right) for Lmx1b^f/f (black) and Lmx1b^f/f/p (red) mice while DRN perfused with acidified aCSF (acidosis; open bars) compared with normal aCSF (control; solid bars). n = 10 per group. *p < 0.001. F, Nissl-stained section to verify cannula placement toward DRN. Arrow indicates cannula tract. Scale bar, 100 μm. Aq, Aqueduct of Sylvius. G–I, Bar graphs represent mean effects of perfusion of normal or acidified aCSF into DRN on respiratory frequency (G), tidal volume (H), and minute ventilation (I) for Lmx1b^f/f (black) and Lmx1b^f/f/p (red) mice during Wake (left) and NREM (right). n = 10 per group.