MECHANISMS OF ACUPUNCTURE INTERVENTION IN RATS OF POST-STROKE DEPRESSION

Objective: To observe the effect of Jieyuanshen acupuncture on brain neurotransmitters in post-stroke depression (PSD) rats, and to explore the mechanism by which acupuncture improves PSD. Methods: Rats were randomly divided into normal, model, drug, and acupuncture groups. A post-stroke depression model was made by middle cerebral artery occlusion and chronic unpredictable mild stress. The acupuncture group was treated at Baihui, Fengfu, Shenmen and Taichong points for 20 min. The rats in the treatment group were treated with fluoxetine (2 mg/kg) once a day for 7 days. 3 courses, each course of rest between 1 day. Pathological changes in the hippocampal CA1 region were observed by light microscopy. Ultrastructural changes of the hippocampus were observed by electron microscopy. Levels of seretonin (5-HT), norepinephrine (NE), acetylcholine (Ach), gamma-aminobutyric acid (gamma-GABA) and glutamate (Glu) were measured in the cerebral cortex. 5-HT transporter (5-HTT), 5-HT1A receptor (5-HT1A R), NE alpha 2 receptor (NE alpha 2R) mRNAs and proteins were detected by RT-PCR and immunoblotting, respectively, in the hippocampus and raphe nucleus. Results: Compared with the model group, the acupuncture group had a lower Zea Longa score, higher sugar consumption, higher exercise level and greater number of vertical movements in the open field test (P <0.01 or P <0.05). The ultrastructural changes of hippocampal neurons were obvious and the damage to neurons was severe. There were fewer ultrastructural changes in hippocampal neurons in the acupuncture and drug groups compared with those in the model group. After treatment, levels of 5-HTT and 5HT1A R mRNA and protein in the brain tissue of PSD model rats were decreased, and levels of Ach, gamma-GABA, and Glu, and 5-HTT and 5-HT1A R mRNA and protein were significantly higher in the cortex of the acupuncture group compared with those in the untreated group (P <0.01). The mRNA and protein levels of NE alpha 2R mRNA and protein in the hippocampus, (P <0.01). The mRNA and protein levels of Ach, gamma-GABA, Glu and NE alpha 2R were decreased (P <0.01 or P <0.05). Conclusion: Jieyuanshen acupuncture can significantly improve the behavioral changes of post-stroke depression rats, and may up-regulate the levels of 5-HT and NE in the cerebral cortex, down-regulate the expression of Ach, gamma-GABA and Glu, and promote hippocampus, 5-HTT, 5-HT1A R, NE alpha 2R, inhibit the expression of NE alpha 2R, reduce the organic damage of hippocampus, and provide neuroprotective effect.