Objective: To provide experimental basis for guiding preparation process of Shenling granules by investigating hypnotic efficacy on extraction and purification process. Method: Four groups of extract with different process were prepared. Effects of each extract on synergistic action of pentobarbital sodium with sub-threshold dose and threshold dose on mice were investigated by righting reflex test. Multiple factors model were established with Yin and blood-deficiency induced by cyclophosphamide and hydrocortisone

and sleep deprivation 48 h induced by water platform method. Content levels of amino acid neurotransmitters in brain tissue of rats were determined by HPLC

glutamate (Glu)

glycine (Gly)

taurine (Tau) and γ-aminobutyric acid (GABA)

to name a few. Result: Four groups of extract had different synergistic effect on pentobarbital sodium with sub-threshold dose and threshold dose on mice

especially the group of single volatile oil extraction and alcohol precipitation can significantly shorten sleep latency of mice and prolong sleeping time of mice. Compared with the blank group

contents of Glu

Tau

GABA and ratio of them in brain tissue of the insomnia model rats showed a considerable elevation. While contents of these indicators decreased in different degree after treatment of extract

among them the group of single volatile oil extraction and alcohol precipitation showed more significant

ratio of Glu/(Tau+GABA) was reduced simultaneously. Conclusion: Process route of single volatile oil extraction and alcohol precipitation is the best preparation process of Shenling granules.