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Investigation of sedative and hypnotic effects of Amygdalus communis L. extract: behavioral assessments and EEG studies on rat


Amygdalus communis L. (almond) has been traditionally used as a natural medicine in the treatment of various diseases. The present research studied the sedative and hypnotic effects of the aqueous fraction of seeds of almond in rats. In order to investigate these effects, a combination of behavioral methods (open field test and loss of righting reflex test) as well as quantitative and analytic methods (EEG and EMG) were applied. The results of the open field test showed that a dose of 400 mg/kg of the almond extract significantly inhibited the locomotion activity of rats compared to normal. The results also illustrated that the almond extract affected pentobarbital-induced sleep through increasing the number of fallings asleep and prolongation of sleeping time. Analysis of EEG recordings of the animals which had received the same dose of the almond extract as the open field test demonstrated marked changes in the animals’ sleep architecture. Significant prolongation of total sleeping time as well as significant increase in NREM sleep were the main observed changes compared to the normal condition. These results suggest that the aqueous extract of almond has significant sedative and hypnotic effects, which may support its therapeutic use for insomnia.

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This work has been fulfilled as part of a Ph.D. thesis financed by Traditional Medicine and Materia Medica Research Center, Shahid Beheshti University of Medical Sciences. Authors would like to thank the center for their help and support during the present research.

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Correspondence to Mehrdad Faizi.

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Abdollahnejad, F., Mosaddegh, M., Kamalinejad, M. et al. Investigation of sedative and hypnotic effects of Amygdalus communis L. extract: behavioral assessments and EEG studies on rat. J Nat Med 70, 190–197 (2016).

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  • Amygdalus communis L.
  • Traditional medicine
  • Aqueous extract
  • Sedative and hypnotic effects