[ acupuncture modulates Glu/GABA‑Gln metabolic loop abnormalities in insomniac rats].

OBJECTIVES

To investigate the therapeutic effect of acupuncture in a rat model of insomnia and its regulatory effect on the glutamic acid (Glu)/γ-aminobutyric acid (GABA)-glutamine (Gln) metabolic loop.

METHODS

Forty male SD rats were randomly assigned to control group, model group, group and group (=10). In the latter 3 groups, rat models of insomnia were established by intraperitoneal injections of p-chlorophenylalanine and verified using a sodium pentobarbital-induced sleep test. After modeling, the rats in and groups received acupuncture for 7 days at specifically chosen sets of acupoints based on the rationale in traditional Chinese medicine. Pathological changes in the hypothalamic tissue of the rats were examined with HE staining, and the levels of Glu and GABA in the hypothalamus were determined with high-performance liquid chromatography (HPLC)-mass spectrometry (MS)/MS. Immunohistochemistry was used to detect the expressions of GABAA receptors (GABAARs) in the hypothalamus, and the expression levels of glutamate decarboxylase (GAD65/67) and glutamine synthetase (GS) were determined with Western blotting.

RESULTS

Compared with the model group, the rats in and groups exhibited decreased Glu levels and GABAA receptor expression and increased GABA levels with a decreased Glu/GABA ratio in the hypothalamus. acupuncture significantly increased the protein expressions of GAD65 and GAD67 and lowered the expression of GS in the hypothalamus in the rat models of insomnia.

CONCLUSIONS

acupuncture produces sedative and hypnotic effects in rat models of insomnia possibly by regulating Glu and GABA-Gln metabolism to restore the excitatory/inhibitory balance between Glu and GABA.