Table 1.
Resting parameters in wild-type and endothelial nitric oxide synthase knock-out mice.
| Parameter | Male | Female | ||
|---|---|---|---|---|
| WT | eNOS–/– | WT | eNOS–/– | |
| Number of mice | 12 | 13 | 12 | 12 |
| Age, days | 78.0 ± 0.2 | 80.8 ± 2.2 | 79.0 ± 0.2 | 76.0 ± 2.2 |
| Body weight, g | 24.9 ± 0.5 | 23.7 ± 0.6 | 19.1 ± 0.3* | 18.2 ± 0.4‡ |
| Frequency, breaths/min | 186 ± 8 | 185 ± 6 | 182 ± 4 | 172 ± 3 |
| Tidal volume, ml | 0.205 ± 0.005 | 0.196 ± 0.009 | 0.167 ± 0.006 | 0.169 ± 0.004 |
| Minute ventilation, ml/min | 37.4 ± 1.3 | 35.6 ± 1.3 | 29.9 ± 0.8 | 29.0 ± 1.1 |
| Inspiratory time, sec | 0.115 ± 0.002 | 0.113 ± 0.003 | 0.120 ± 0.002 | 0.126 ± 0.002 |
| Expiratory time, sec | 0.227 ± 0.007 | 0.225 ± 0.008 | 0.226 ± 0.007 | 0.240 ± 0.005 |
| Inspiratory time/expiratory time | 0.520 ± 0.016 | 0.509 ± 0.011 | 0.543 ± 0.014 | 0.538 ± 0.012 |
| Inspiratory drive, ml/sec | 1.82 ± 0.08 | 1.75 ± 0.07 | 1.41 ± 0.04 | 1.36 ± 0.05 |
| Expiratory drive, ml/sec | 0.92 ± 0.03 | 0.88 ± 0.03 | 0.75 ± 0.02 | 0.72 ± 0.03 |
| Peak inspiratory flow (PIF), ml/sec | 2.97 ± 0.14 | 2.89 ± 0.12 | 2.29 ± 0.06 | 2.28 ± 0.08 |
| Peak expiratory flow (PEF), ml/sec | 1.96 ± 0.09 | 1.90 ± 0.0.10 | 1.57 ± 0.07 | 1.50 ± 0.05 |
| PIF/PEF | 1.53 ± 0.05 | 1.56 ± 0.06 | 1.49 ± 0.05 | 1.53 ± 0.03 |
The data are presented as mean ± SEM. WT, wild-type C57BL6 mice. eNOS–/–, endothelial nitric oxide synthase knock-out mice. There were no differences in ages, body weights and resting ventilatory parameters between male WT and eNOS–/– mice and between female WT and eNOS–/– mice (*P < 0.05, body weights, male WT versus female WT mice; and ‡P < 0.05, body weights, male eNOS–/– versus female eNOS–/– mice).