IN 1936 Bacq1 demonstrated that, in addition to sensitizing certain smooth muscles of the cat to stimulation of sympathetic nerves and to injected adrenaline, some poly-hydroxylic phenols also possessed convulsant activity. The sensitization was originally attributed to the anti-oxidant properties of the phenolic compounds. More recent studies, however, have indicated that polyphenols augment the peripheral actions of adrenaline by competitive inhibition of catechol-O-methyl transferase (COMT) (refs. 2–4). It has also been suggested that the central effects of polyphenols may be caused by a similar mechanism5. Our study was undertaken to investigate the possible role of adrenergic mechanisms in the central effects of these compounds.