Figure 5.

Mouse arterial oxygen saturation, BP, and heart rate (HR) during IH delivered at variable frequencies simulating OSA with an oxygen desaturation index (ODI) of 15, 30, or 60/h using the apparatus shown in Figure 3. The nadir fraction of inspired oxygen of 11% was empirically determined, targeting an arterial oxygen saturation nadir of 80%. Note the low basal HR due to thermoneutral conditions of the study and the acceleration of HR during each desaturation. Reprinted with permission from Jun and colleagues (34). BPM, beats per minute.