Fig. 2. Time course of plasma epinephrine (  A ) and norepinephrine (  B ) concentrations (ng/ml) in nicardipine and anaphylaxis groups. Time 0 (T0) corresponds to injection of nicardipine or ovalbumin. (  A ) Anaphylaxis was characterized by a stronger sympathetic activation with higher plasma epinephrine concentrations occurring early after the injection of ovalbumin and sustained during the entire study (from 0.38 ± 0.17 [T0−5] to 5.86 ± 0.67 ng/ml [T60]; *  P < 0.0001). Despite arterial hypotension of similar magnitude, the nicardipine group had a smaller increase in plasma epinephrine concentrations (from 0.55 ± 0.27 [T0−5] to 2.25 ± 0.43 ng/ml [T60]; *  P < 0.0001). A between-group difference was observed at T20, T40, and T60 (†  P < 0.05). (  B ) Anaphylaxis was characterized by a stronger sympathetic activation with plasma norepinephrine concentrations occurring early after the injection of ovalbumin and sustained during the entire study (from 0.48 ± 0.19 [T0−5] to 4.44 ± 0.80 ng/ml [T60]; *  P < 0.0001). Despite arterial hypotension of similar magnitude, the nicardipine group had a smaller increase in plasma norepinephrine concentrations (from 0.37 ± 0.06 [T0−5] to 2.39 ± 0.70 ng/ml [T60]; *  P < 0.0001).