Table 2.
Raw data from Initial Baseline and End Points under different steady-state brainstem PCO2 conditions from Experiment 1, Single Bout CB Hypoxia Within Animal
| Respiratory variable | Baseline | End Point |
|---|---|---|
| 25 Torr PCO2 brainstem = 8 | ||
| fR (min−1) | 30.87 ± 4.4 | 32.04 ± 4.82 |
| nVT (a.u.) | 3.5 ± 0.32 | 3.29 ± 0.28*1 |
| nVE (a.u.) | 109.24 ± 17.47 | 103.91 ± 15.77 |
| TI (s) | 0.97 ± 0.066 | 0.99 ± 0.089 |
| TE (s) | 1.49 ± 0.52 | 1.81 ± 0.93 |
| EI | 0.67 ± 0.24 | 0.68 ± 0.24 |
| 50 Torr PCO2 brainstem n = 8 | ||
| fR (min−1) | 31.7 ± 2.012 | 32.39 ± 1.88 |
| nVT (a.u.) | 4.42 ± 0.24+,2 | 4.27 ± 0.24*1 |
| nVE (a.u.) | 140.81 ± 13.23+2 | 139.61 ± 13.54 |
| TI (s) | 0.73 ± 0.072+2 | 0.73 ± 0.067 |
| TE (s) | 1.23 ± 0.14 | 1.18 ± 0.12 |
| EI | 0.60 ± 0.036+2 | 0.58 ± 0.033 |
a.u., arbitrary units; TI, inspiratory duration; TE, expiratory duration; EI, eupnoeic index. These data illustrate the phrenic neurogram characteristics during the baseline period prior to and during a washout period following the experimental perturbation. Note that the baseline frequency is no different under any brainstem PCO2 condition.
*
End Point variable is significantly different than the same variable for Baseline.
+
Variable at 50 Torr PCO2 brainstem is significantly different than the same variable under conditions of 25 Torr PCO2 brainstem.