Effect Of Essential Oils On Central Nervous System
Although plant-derived essential oils have been used to treat various mental disorders, their central nervous system acting effects have not been clarified. The present study compared the effects of 20 kinds of essential oils with the effects of already-known central nervous system acting drugs to examine whether the essential oils exhibited CNS stimulant-like effects, CNS depressant-like effects, or neither.
All agents were tested using a discrete shuttle-type conditioned avoidance task in mice. Essential oils of peppermint (Mentha piperita) and chamomile (Anthemis nobilis) exhibited central nervous system stimulant-like effects; that is, they increased the response rate (number of shuttlings/min) of the avoidance response.
Linden also increased the response rate, however, the effect was not dose-dependent. In contrast, essential oils of orange, grapefruit, and cypress exhibited central nervous system depressant-like effects; that is, they decreased the response rate of the avoidance response.
Essential oils of eucalyptus (Eucalyptus globulus) and rose (Rosa damascena) decreased the avoidance rate (number of avoidance responses/number of avoidance trials) without affecting the response rate, indicating that they may exhibit some central nervous system acting effects.
Essential oils of 12 other plants, including juniper, patchouli, geranium, jasmine, clary sage, neroli, lavender, lemon, ylang-ylang, niaouli, vetivert and frankincense had no effect on the avoidance response in mice.
Copyright © 2011 John Wiley & Sons, Ltd.