Fig. 5

Respiratory responses to hypercapnia in WT and Ndn +m/−p mice. a Representative tracing of plethysmography data for WT and Ndn +m/−p mice at postnatal days (P) 4 and 8. b–d Ventilatory responses to hypercapnia in Ndn +m/−p and WT mice (n = 8 for both groups) at P4 revealed that WT mice had significantly increased breathing frequency while breathing 7% CO₂ (c). e–g Ventilatory responses to hypercapnia in Ndn +m/−p and WT mice (n = 11 for both groups) at P8 revealed that WT mice had significantly increased minute ventilation while breathing 7% CO₂ (e). Statistical analyses were performed using Student’s t test. Data are presented as mean ± SEM