Figure 3.

Responses of lung vagal C fibers to intravenous injection of three types of stimulants in two rats after exposure to room air or chronic intermittent hypoxia. Duration of exposure to room air (RA; A) or chronic intermittent hypoxia (CIH; B) was 14 days. At 16 h after the last exposure, afferent responses to intravenous capsaicin, adenosine, and α,β-meATP were measured. These stimulants were injected into the jugular vein as a bolus (0.1 ml volume) as indicated by the arrows. Approximately 15 min elapsed between any two injections. AP, action potential; Ptr, tracheal pressure; ABP, arterial blood pressure. See the legend of Figure 1 for further explanation.