Partial pressures of O2 in the red muscle and arterial blood of rainbow trout under control normoxic conditions, and the effects of reducing water PO2in mild hypoxia
| . | PwO2 (mmHg) . | . | . | ||
|---|---|---|---|---|---|
| . | 140 (normoxia) . | 100 . | 75 . | ||
| PrmO2 (mmHg) | 61±10a | 51±6b | 41±5c | ||
| PaO2 (mmHg) | 119±5d | 84±2e | 61±3a,b | ||
| PaO2—PrmO2(mmHg) | 58±10a | 33±6b | 20±4c | ||
| Change in PrmO2 from normoxia (%) | - | -13±7a | -29±8b | ||
| Change in PaO2 from normoxia (%) | - | -29±3b | -48±3c | ||
| . | PwO2 (mmHg) . | . | . | ||
|---|---|---|---|---|---|
| . | 140 (normoxia) . | 100 . | 75 . | ||
| PrmO2 (mmHg) | 61±10a | 51±6b | 41±5c | ||
| PaO2 (mmHg) | 119±5d | 84±2e | 61±3a,b | ||
| PaO2—PrmO2(mmHg) | 58±10a | 33±6b | 20±4c | ||
| Change in PrmO2 from normoxia (%) | - | -13±7a | -29±8b | ||
| Change in PaO2 from normoxia (%) | - | -29±3b | -48±3c | ||
PrmO2, partial pressure of O2 in the red muscle; PaO2, partial pressure of O2 in arterial blood; PwO2, water PO2.
All values are means ± s.e.m., N=6.
The PrmO2 value for each fish,used to derive the mean value shown here, was calculated as the mean of 30 measurements made every 1 min during either normoxia or either level of hypoxia, whereas the PaO2 for each fish was calculated as the average of two measurements, made at the beginning and end of the 30 min period (see text for further details).
The PaO2—PrmO2is the partial pressure gradient between arterial blood and the RM.
For the PaO2 and PrmO2 data, a common superscript indicates no significant difference by two-way repeated-measures ANOVA with Bonferroni post-hoc comparisons amongst means. The same ANOVA was performed on the % change data, following their arc-sine transformation.
For the PaO2—PrmO2data, a common superscript indicates no significant difference by one-way repeated-measures ANOVA with Bonferroni post-hoc comparisons amongst means.
In all cases, significance was attributed at P<0.05.