Fig. 5. The effects of acute hypoxia (40 mmHg=5.3 kPa; at the vertical dashed line) on plasma levels of adrenaline (filled columns) and noradrenaline (open columns) in rainbow trout (Oncorhynchus mykiss) previously infused (0.2 ml min–1) with saline for 60 min under conditions of normoxia. An injection of (A) saline (control; N=9) or (B) lisinopril (10–4 mol kg–1; N=10) was made prior to hypoxia at 40 min saline infusion. Plasma catecholamine levels were measured at ‘Pre’, 10 min and 60 min of infusion and during acute hypoxia. Values are shown as means + S.E.M. An asterisk denotes a statistically significant increase (P<0.05) from the corresponding ‘60 min’ pre-hypoxia value. A dagger indicates a statistically significant difference (P<0.05) from the control value.
