Conclusions
LD can be considered to develop health-care food or novel drugs to cope with the increasing number of insomniacs.
Methods
Wistar rats were intraperitoneally injected with p-chlorophenylalanine (PCPA) to establish an insomnia model. Rats were divided into six groups (n = 8): Control, PCPA, Estazolam (0.5 mg/kg), LD extract in low, medium and high doses (185.22, 370.44, 740.88 mg/kg). Serum hormone levels of the HPA axis, levels of 5-HT, NE and MT, and the expression of GABAA and 5-HT1A receptors in hypothalamus were determined. Moreover, behavioural and pathological changes in the hypothalamus were evaluated.
Objective
To investigate the alleviating insomnia mechanism of L. davidii (LD). Materials and
Results
After LD administration, body weight and brain coefficient increased by 2.74% and 8.22%, respectively, and the adrenal coefficient decreased by 25%, compared with PCPA group. Elevation of the serum hypothalamic-pituitary-adrenal (HPA) axis hormone CRH (11.24 ± 3.16 ng/mL), ACTH (565.87 ± 103.44 pg/mL) and CORT (44.28 ± 8.73 ng/mL) in the PCPA group was reversed after LD treatment. Furthermore, abnormal excitatory behaviour [5 min movement distance (2096.34 ± 259.51 cm), central exercise time (5.28 ± 1.08 s)] of insomnia rats in the PCPA group was also relieved. LD extract increased 5-HT and MT levels, reduced NE level in the hypothalamus, and upregulated the expression of GABAA R and 5-HT1A. Moreover, LD extract may improve the pathology of neurons in the hypothalamus. Conclusions: LD can be considered to develop health-care food or novel drugs to cope with the increasing number of insomniacs.