Figure 3.
Unilateral ablation of pre-Bötzinger complex NK1R neurons does not significantly alter responses to hypoxia and hypercapnia during wakefulness. In response to hypercapnia (5% CO2, 21% O2, 84% N2), there was a significant increase in respiratory frequency compared with that in room air both pre- and postinjection (P < 0.05); the responses postinjection were not significantly different (P > 0.05) from preinjection responses or from those of rats injected with substance P mixed with saporin (unconjugated, control). Similarly, hypoxia (12% O2, 88% N2) induced significant increases (P < 0.05) in frequency both pre- and postinjection compared with that in room air; these responses were not significantly different (P > 0.05) from preinjection responses or from control animals. *P < 0.05, significantly different from responses in room air. SP-SAP = saporin conjugated to substance P.