FIG. 5.

Short-term hypoxic phrenic responses. (A) Average ipsilateral integrated phrenic nerve burst amplitude (volts) during the first (H1), second (H2), and third (H3) hypoxic episodes in each rat. Average phrenic nerve amplitude was reduced ipsilateral to injury during hypoxic episodes vs. intact rats, despite similar levels of arterial PaO₂. No intermittent hypoxia (IH) protocol-specific differences were observed, nor was there evidence for progressive augmentation in any group. (B) Average contralateral integrated phrenic nerve burst amplitude during the first, second, and third hypoxic episodes. Average phrenic nerve amplitude was not different between groups, nor was there evidence for progressive augmentation in successive hypoxic episodes. *Significantly different from intact 28 days of normoxia (Nx28); p < 0.05.