Chemoreflex drive of ventilation in the awake miniature pig

Awake, resting miniature pigs trained to breathe through a respiratory mask were studied at neutral ambient temperature first intact, then after bilateral chronic carotid body denervation. Resting pulmonary ventilation (V), tidal volume (VT) and ventilatory period (T), and O2 and CO2 partial pressures in the end-tidal gas (PETO2, PETCO2) were measured cycle-by-cycle in steady state at levels of PETO2 ranging from 35 to 300 Torr, and in the …