Anxiolytic‐like effect of essential oil extracted from <i>Abies sachalinensis</i>

Abstract

ABSTRACT It has been proposed that essential oil extracted from Abies sachalinensis (EOAS) has a relaxation effect, among others, in humans; however, the scientific evidence is currently insufficient. To clarify the influence of EOAS on emotional behaviour, we examined its anxiolytic‐like effect using a mouse model. The elevated plus maze task was used to evaluate the anxiolytic‐like effect. The results showed that intraperitoneal (i.p.) administration of EOAS at 0.6 g/kg body weight did not produce an anxiolytic‐like effect. However, a significant anxiolytic‐like effect was observed after inhalation of EOAS at 3.6 mg/l air ( P &lt; 0.05). Next, the effect of the route of administration (i.p. vs. inhalation) on the distribution of the major components of EOAS was analysed. α ‐Pinene was observed in the brain at 5.7 ± 2.0 mg/kg (i.p.) and 19.7 ± 0.9 mg/kg (inhalation). The data showed that EOAS effectively produced an anxiolytic‐like effect after administration by inhalation. Thus, the efficacy of EOAS in producing an anxiolytic‐like effect is likely to be due to achieving adequate levels in the brain after EOAS had been inhaled. Copyright © 2011 John Wiley &amp; Sons, Ltd.