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Fig. 2. Mean heart rate (fH) ± S.E.M. during (A)
post-dive surface intervals and (B) dives in control and pharmacologically
blocked harbour seals (N=5). Heart rate data from control groups were
combined to give the mean fH indicated by the horizontal
lines, although statistical analyses were performed on controls for each data
set. * indicates values significantly different from the control
group within dive states (P<0.05). For each treatment, the dive
fH was significantly lower than the surface interval
fH.
, seals treated with
-adrenergic
blocker; ß, seals treated with ß-adrenergic blocker; mu+
,
seals treated with muscarinic and
-adrenergic blockers combined;
mu+ß, seals treated with muscarinic and ß-adrenergic blockers
combined.