Further Studies on the Fluctuation of Chemoreceptor Discharge in the Cat

Abstract

The response of carotid body chemoreceptors to differing but steady levels of arterial blood gas tensions and pH has been extensively documented (e.g., 3), and further studies have shown that some form of interaction between hypoxic and hypercapnic stimuli occurs at chemoreceptor level (9,11). These observations are of value but of limited physiological importance because it is clear that these stimuli in arterial blood are rarely, if ever, steady. In addition to breath-tobreath variations in tidal volume, breatholding as in phonation, drinking etc., there is clear evidence of within-breath fluctuations of blood gas tension (16) and pH (1) to which the chemoreceptors respond with a fluctuation of discharge of similar period (2).