Behavioral variations in response to β-phenylethylamine administration in three rat strains
Dourish CT., Dewar KM.
The behavioural effects of the trace amine β-phenylethylamine have been examined in three rat strains. Systemic injection of β-phenylethylamine produced signs of the 5-HT behavioural syndrome in Sprague Dawley, Long Evans and Wistar rats. The syndrome consisted of headweaving, forepaw padding, splayed hindlimbs, hyperactivity and hyperreactivity. Wistar rats scored lower on total 5-HT behavioural ratings than either Sprague Dawley or Long Evans rats and showed a lower incidence of forepaw padding than Long Evans rats. In contrast, Wistars were more active than Long Evans rats and more hyperreactive than Long Evans or Sprague Dawley rats. These results appear to indicate a difference in sensitivity to stimulation of central 5-HT mechanisms between Wistars and rats of the Long Evans or Sprague Dawley strains. In addition, since hyperactivity and hyperreactivity associated with this syndrome are thought to be mediated by dopaminergic mechanisms, the results suggest that Wistar rats may be more sensitive to dopaminergic stimulation than Long Evans rats.