Sedative and hypothermic effects induced by β‐asarone, a main component of Acorus calamus

In the present study we investigate the behavioural effects of β-asarone, the main compound of the essential oil obtained from Acorus calamus. β-asarone, when administered intraperitoneally in rats, exerts sedative and hypothermic but not analgesic effects. β-asarone, however, when administered in association with the cannabinomimetic drug WIN 55,212-2, was shown to potentiate some of the typical behavioural activities induced in animals by cannabinoids. Binding assays, performed on cortical synaptic membrane preparations using a specific cannabinoid radioligand ([3H]CP-55,940), excluded the ability of β-asarone to exert a direct agonistic activity on CB1 receptors. Hence, β-asarone cannot be considered a pure cannabinomimetic agent but it can be envisaged at least as an allosteric modulatory agent. © 1998 John Wiley & Sons, Ltd.