Central ventilatory responses to O2 and CO2 at three levels of carotid chemoreceptor stimulation

Two series of experiments were performed on anesthetized dogs to study the steady-state ventilatory responses of the central respiratory mechanism to hypoxia and hypercapnia at three different levels of cartoid body stimulation. A cross-perfusion technique was used to perfuse a recipient dog's carotid bodies with blood of desired oxygen tension from a donor dog. Central hypoxia and hypercapnia were induced by allowing the recipient dog to spontaneously breathe specific gas mixtures for 6-min periods.