A recent publication in the Georgetown University Institutional Repository emphasizes the specific actions by which electro-acupuncture relieves chronic stress and anxiety. Citing a multiplicity of studies showing the effectiveness of acupuncture for the treatment and anxiety, the researchers compared its physiological mechanisms of effective action. The researchers note that two main pathways are involved in the stress reducing effects of electro-acupuncture, the hypothalamic-pituitary-adrenal axis (HPA) and the sympathetic nervous system (SNS).

Acupuncture relieves stress.The HPA hormones responsive to electro-acupuncture therapy are brain corticotrophin releasing hormone (CRH), plasma adenocorticotropin hormone (ACTH) and serum corticosterone (CORT). The sympathetic nervous system markers were primarily adrenal tyrosine hydroxylase (TH), a norepinephrine synthesis enzyme, plasma neuropeptide Y (NPY) and norepinephrine. The researchers then examined blockage of the HPA and SNS pathways in an effort to determine which has the predominant role in electro-acupuncture induced stress reduction.

Electroacupuncture effectively reduced adrenal mRNA expression levels of NPY and TH even when NE levels remained constant. This finding confirms that the HPA pathway has a primary role in electroacupuncture induced stress reduction. The research was confirmed with significant decreases of mRNA expression and immunoreactivity of CRH and NPY in the paraventricular nucleus. Behavioral studies also confirmed the results. As a result of these findings, the researchers concluded that "although the SNS was modulated by EA (electroacupuncture), the HPA may be the main pathway responsible for the chronic-stress allaying effects of EA."

Reference:
Eshkevari, Ladan. "The Stress Reducing Effects of Acupuncture in a Rat Model of Chronic Stress."