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Fig. 2. Olfactory responses of Carassius auratus to changes in
environmental [Na+], [Mg2+] and [K+]. (A)
Typical electroencephalogram (EEG) recordings from the olfactory bulb (lower
traces) and their integrated activity (upper traces) in response to 100 mmol
l-1 Na+ (in Na+-free AFW), 100 mmol
l-1 Mg2+ in AFW and 10 mmol l-1 K+
in AFW (horizontal bars). All three recordings were taken from the same fish.
(B) Semi-logarithmic plot of pooled, normalised (to the response to
10-5 mol l-1 L-serine in AFW) data of integrated EEG
amplitude (means ± S.E.M.; N=5-6) in response to changes in
[Ca2+] (filled circles), [Mg2+] (filled triangles),
[Na+] (open circles) and [K+] (open triangles). Note
that only the responses to Na+ approach the amplitude of those
evoked by Ca2+, and then only at high concentrations.