Effects of Different Waveform Electroacupuncture on the 5-HT, Glu and CABA Contents of the Hypothalamus in Rats with PCPA-induced Insomnia / 上海针灸杂志

ABSTRACT

Objective To investigate the effects of electroacupuncture of different stimulation waveforms on the 5-hydroxytryptamine (5-HT), glutamic acid (Glu) and gamma-aminobutyric acid (CABA) contents of the hypothalamus in rats with para-chlorophenylalanine (PCPA)-induced insomnia and explore the difference in the effects and the mechanism of its action. Methods Fifty SD rats were randomly allocated to a normal group of 10 rats, a model group of 10 rats and an electroacupuncture group of 30 rats. The electroacupuncture group was then randomly divided to electroacupuncture groups 1, 2 and 3, 10 rats each. A rat model of insomnia was made using PCPA in all groups of rats except the normal group. All the electroacupuncture groups received electroacupuncture treatment. Of them, electroacupuncture group 1 received sparse wave treatment; electroacupuncture group 2, dense wave treatment;electroacupuncture group 3, sparse-dense wave treatment. After 6 days of treatment, every group of rats was sacrificed by cervical dislocation. The 5-HT, Glu and CABA contents of the hypothalamus were measured by enzyme-linked immunosorbent assay. Results The 5-HT content of the brain decreased significantly in the model group of rats compared with the blank group (P<0.01) and increased significantly in electroacupuncture group 3 of rats compared with the model group (P<0.01). There was a statistically significant difference in brain 5-HT content between electroacupuncture group 2 or 3 of rats and electroacupuncture group 1 (P<0.05,P<0.01) and between electroacupuncture groups 3 and 2 of rats (P<0.01). The Glu and CABA contents of the cerebral cortex and the ratio of Glu/CABA increased significantly in the model group of rats compared with the blank group (both P<0.01) and decreased significantly in electroacupuncture group 3 of rats compared with the model group (both P<0.01). There were statistically significant differences in the Glu and CABA contents of the cerebral cortex between electroacupuncture group 2 or 3 of rats and electroacupuncture group 1 ((P<0.05,P<0.01) and between electroacupuncture groups 3 and 2 of rats (P<0.01). Conclusions Electroacupuncture can regulate hypothalamic monoamine neurotransmitter 5-HT content and amino acid neurotransmitters Glu and CABA contents and reduce intracerebral amino acid toxicity to produce a therapeutic effect on insomnia in insomnia rats. The therapeutic effect of sparse wave electroacupuncture is superior to that of dense wave or sparse-dense wave electroacupuncture.