Table 4.

Plasma concentrations of stress hormones, plasma osmolality and metabolic rate in eels exposed for at least 6 weeks to water CO2 partial pressures (PwCO2) of approx. 0.8 mmHg (ambient control), 15±1 mmHg, 30±1 mmHg or 45±1 mmHg

PwCO2 (mmHg)
Approx. 0.815±130±145±1
Adrenaline (nmol l-1)3.11±0.313.42±0.333.11±0.623.92±0.31
Noradrenaline (nmol l-1)5.31±0.905.72±1.107.32±1.226.90±1.11
Cortisol (nmol l-1)22.30±3.7233.61±6.3327.62±7.8227.80±10.51
Osm (mosmol kg-1)292±6296±4309±12300±4
RMR (mmol O2 kg-1 h-1)-0.94±0.371.16±0.371.07±0.18
SMR (mmol O2 kg-1 h-1)0.85±0.100.61±0.130.74±0.310.80±0.24
  • 1 mmHg=approx. 0.01316 kPa.

    Osm, osmolality; RMR, routine metabolic rate; SMR, standard metabolic rate (please see text for details).

    Values are means ± 1 S.E.M.

    For plasma hormones and osmolality, N=5-7 determinations.

    For metabolic rate, N=8 in all cases.

    There were no significant differences amongst groups for any variable (P>0.05).