Ventilatory and metabolic responses to hypoxia in vehicle (n=8, from four litters) and mifepristone (n=10, from two litters) pups. Minute ventilation (V̇E), tidal volume (VT in ml/100 g), respiratory frequency (fR in breaths/min), O2 uptake (V̇O2) CO2 production (V̇CO2) and O2 ans CO2 ventilatory equivalents (V̇E/V̇O2 and V̇E/V̇CO2) under normoxia or after 10 or 30 min of hypoxic exposure. Values are mean±SEM.