Acupuncture blocks cold stress-induced increases in the hypothalamus–pituitary–adrenal axis in the rat

Abstract

Electroacupuncture (EA) is used to treat chronic stress; however, its mechanism(s) of action in allaying stress remains unclear. The interplay of stress hormones of the hypothalamuspituitary-adrenal axis (HPA) and the sympathetic nervous system (SNS) is critical in the stress response. Our objective was to determine whether EA at acupoint, stomach 36 (EA St 36 ) is effective in preventing chronic cold stress-induced increased hormone levels in the rat by examining four groups of animals, three of which were exposed to cold and one of which was a non-treatment control group. Before exposure to the cold, two groups were treated with either EA St 36 , or Sham-EA, before 10 days of cold stress. The EA St 36 animals demonstrated a significant decrease in peripheral HP hormones (ACTH and CORT) compared with stress animals (P!0.05). These effects were specific; rats receiving Sham-EA had elevation of these hormones, similar to the stress-only animals. These effects were mirrored centrally in the brain; CRH levels were significantly (P!0.05) reduced in EA St 36 animals compared with the other animals. Finally, EA effect on peripheral and adrenal SNS hormones (norepinephrine (NE) and neuropeptide Y (NPY) respectively) was examined, with no significant difference noted in adrenal tyrosine hydroxylase or circulating NE in any of the groups. However, EA St 36 was effective in preventing stress-induced elevation is adrenal Npy mRNA. These results indicate that EA St 36 blocks the chronic stress-induced elevations in the HPA and the sympathetic NPY pathway, which may be a mechanism for its specific stress-allaying effects.

Early electroacupuncture treatment ameliorates neuroinflammation in rats with traumatic brain injury

“…Furthermore, in SD rat models equivalent to those used in our study, Du et al demonstrated the same results in an abdominal adhesion model even though the rats’ weights were less than those in our study [33]. Finally, Eshkevari et al described the same results in a cold stress model in rats with weights similar to those in our study [34]. Therefore, our study did not include a non-acupoint group, but focused on comparing whether EA delivered at acupoints could notably improve the injured cortex after TBI.…”

“…The non-acupoints are usually situated adjacent to actual acupoints, and in several experimental animal models, they have been separated by a distance of <5 mm [29, 32, 33] or have been far away from the actual acupoints [34]. For example, Zhang et al showed that the therapeutic effects of EA applied to actual acupoints on TNF-α expression were better than the effects of EA administered at non-acupoints in a Wistar rat abdominal adhesion model [32], and Yu et al reported the same effects in an endotoxic shock-related lung injury model in rabbits [29].…”

Acupuncture as a Treatment Modality in Dermatology: A Systematic Review

“…19,20,22,24 Modern investigations into possible mechanisms of acupuncture have mixed results on the validity of meridians, but consistent across studies is involvement of the autonomic nervous system and hypothalamus-pituitary-adrenal (HPA) axis, recruited via peripheral sensory receptors. [37][38][39][40][41][42][43][44] Functional magnetic resonance imaging studies on humans found modulation of areas in the central nervous system involved in stress and nociception, such as the hypothalamus, nucleus accumbens, amygdala, hippocampus, and anterior cingulate gyrus. 39,[41][42][43][44] The downstream release of endogenous opioids is thought to contribute to subsequent analgesic and antipruritic effects.…”

Acupuncture Effect and Central Autonomic Regulation

“…The PVN of hypothalamus is a cell group that plays an important role in the regulation of sympathetic vasomotor tone and autonomic stress responses [31, 32]. Acupuncture could decrease NPY [33] and corticotropin-releasing hormone [34] expressions in the PVN and produce some specific effects on suppressing the sympathetic outflow in response to chronic stressors [35]. …”