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Fig. 5. Cross-adaptation experiments suggest the presence of relatively independent
receptor sites for each of the polyamine odorants tested. The
electro-olfactogram (EOG) responses to each test odorant in (A) putrescine
(Put), (B) cadaverine (Cad), (C) histamine (His), (D) spermidine (Spd), (E)
spermine (Spm), (F) agmatine (AGB) and (G) L-glutamine (Gln) competitor
odorant backgrounds are expressed as a percentage of the response obtained to
the odorant prior to switching into the competitor odorant background. Each
competitor odorant was tested on three fish. The dotted line indicates the
level of response predicted if no cross-adaptation is occurring. Asterisks
designate responses significantly greater than the self-adapted response to
the background odorant (one-way ANOVA, Dunnett's post hoc t-test;
P<0.05). Values are means ± S.E.M.