Fig. 2. Reverse-phase HPLC radiochromatograms of the enzymatic products from incubation of honey bee brain extracts with [ring-³H]tyramine. Large arrowhead indicates the elution of synthetic OA and the small arrow indicates the elution of synthetic tyramine as detected by electrochemical detection. Dark trace: radiochromatogram of the enzymatic products from untreated brain extracts. Light trace: compounds recovered from boiled enzyme reaction.