The Hypnotic Effect And Mechanism Of Lavender Essential Oil

Sleep take up one-third of one's life,insomnia may lead to degradation of learning,memory and immunologic function,low work efficiency and high accident rate,emotion problems like anxiety or/and depression,chronic diseases like hypertension and diabetes.One-third population suffer from insomnia every year,medicines used for treating insomnia may have some side effects like excessive sleepiness,drug dependence,excessive sedation,dizzy,headache,cognitive impairment,so people hope to find a method safety,effective and little side effects.Aromatherapy refers to the use of oils extracted from flowers,stems,leaves,roots,and fruits of various plants absorbed into the body through the skin or respiratory system to improve mental and bodily health.Lavender essential oil is one of the most common choices for aromatherapy.Some studies indicate that the main components of lavender essential oil,the linalool and linalyl acetate show sedation and sleep promoting effects,but the characteristics and mechanism are not clear.The present study is designed to use animal experiments to detect the characteristics,passing way and potential mechanism of lavender essential oil's hypnotic effect.Methods:Deliver ing saturated lavender essential oil odor(lavender group)and air(control group)through annular tube(volume: 20 ml/min)to C57 BL/6J mice,recording electroencephalogram and electrmyogram,analysising sleep-wake states of 12 h inactive phase.10% zinc sulfate solution instill in the nares(25 ?l/each side,instill bilateral nares)to establish anosmia model.Using bur ied food test and olfactory habituation/dishabituation test to evaluate whether the mouse is anosmia or not.Recording and analysis model mice sleep-wake states as mentioned before.Using c-Fos immunohistochemistry to mark the activation of neurons in sleep-wake regulating regions,olfactory system and limbic system by lavender.Hoping to reveal the hypnotic characteristic of lavender essential oil,find whether it works through olfactory system and find out possible effective targets.Results:Compared with control,lavender shortens the time from W to NREM,increases NREM and REM in 12 h inactive phase,reduces W.Lavender increases sleep time mainly happen in exchange stage between active phase and inactive phase,by increasing episode number of NREM and REM,and reducing W by decreasing episode duration.As for anosmia model group,lavender essential oil's hypnotic effect has gone.Lavender group shows an obvious increase of Fos-ir neurons in main olfactory bulb,and a decrease in lateral hypothalamic area when compared with air group.Conclusion:Saturated lavender essential oil odor shortens sleep latency,increasing total sleep time act as the increase of NREM and REM in ear ly and final sleep stages.Lavender essential oil promotes sleep may be achieved by the restrain of orexinergic neurons' activity through the olfactory system way.