Research paperEffect of acupuncture stimulation on rats with depression induced by water-immersion stress

•We established a method for creating mild depression in rats.•Mild depression in this rat model appeared to be improved by acupuncture stimulus.•The mechanisms underlying improvement of a depressed state may involve the hypothalamic-pituitary-adrenal axis.

Depression is a kind of mood disorder. The incidence of depressed patients has demonstrated an upward trend in recent years. Symptoms may improve with treatments such as pharmacotherapy and cognitive-behavioral therapy, but such approaches may exert strong side effects, and therapeutic effects can be slow. We studied how acupuncture stimulation would affect depression as a method to reduce side effects. Mild depression was induced in rats by 1-week water-immersion stress. We treated these mildly depressed rats with either acupuncture stimulation at the “Bai-Hui” (GV 20) and “Yintáng” (Ex-HN3) points, or antidepressants. We then measured the immobile time and serum corticosterone level in rats. Immobile time and serum corticosterone level decreased on stimulation with acupuncture or antidepressants. These findings suggest that mild depression in rats was improved by stimulation with acupuncture The mechanisms underlying such improvement may effect HPA system activated by this stress, and inhibit the response to lead to the disorder of the hippocampal nerve cell.