Electroacupuncture Acutely Improves Cerebral Blood Flow and Attenuates Moderate Ischemic Injury via an Endothelial Mechanism in Mice

Electroacupuncture is a promising therapeutic approach that combines traditional needling with modern electrotherapy for the treatment of various neurologic conditions, including ischemic stroke. This health problem remains one of the leading causes of death and disability worldwide, with few truly effective treatment options in the acute phase. Although prior research has demonstrated benefits of electroacupuncture in preventive treatments or rehabilitation after stroke, its immediate application during the acute phase of the ischemic event still required better scientific understanding of the mechanisms involved and its actual efficacy.

This experimental study, conducted by South Korean researchers in mice, aimed primarily to investigate whether electroacupuncture applied immediately after a cerebral ischemic event could improve both tissue damage and functional recovery in the animals. The researchers used two specific acupoints: Baihui (GV-20), located at the top of the head, and Dazhui (GV-14), located in the posterior cervical region. These points were chosen because they are traditionally associated with the treatment of brain and spinal cord disorders in Korean medicine. To test their hypothesis, the researchers artificially induced moderate and severe cerebral strokes in mice by temporarily blocking the middle cerebral artery for 60 or 90 minutes, respectively.

Electroacupuncture treatment was applied immediately after the onset of vascular occlusion, using low-intensity electrical stimuli for 20 minutes.

The results demonstrated that electroacupuncture was able to significantly increase cerebral blood flow, improving perfusion in the cortical region of the brain by approximately 12% relative to baseline levels. This beneficial effect lasted for approximately 20 minutes after the end of treatment. Importantly, this improvement in cerebral circulation was not accompanied by changes in systemic blood pressure, suggesting a local and brain-specific effect. Through experiments with different pharmacologic blockers, the researchers identified that the mechanism responsible for this benefit involves the release of acetylcholine, a neurotransmitter that acts on specific muscarinic receptors in cerebral blood vessels.

This cascade of events results in the production of nitric oxide by vascular endothelial cells, causing vasodilation and consequently increased blood flow. When they tested electroacupuncture in genetically modified mice lacking the enzyme responsible for endothelial nitric oxide production, the benefits disappeared completely, confirming the importance of this molecular pathway.

For patients and healthcare professionals, these findings have important and encouraging clinical implications. Electroacupuncture proved effective specifically in moderate-intensity strokes, reducing the size of the injured brain area by an impressive 34.5% compared to the control group. This reduction in tissue damage translated into significant functional improvements, with treated animals showing better neurologic and motor performance on assessments performed 24 hours after the stroke. These results suggest that electroacupuncture may be a valuable therapeutic tool when applied early in cases of moderate stroke, potentially reducing sequelae and accelerating recovery.

The technique offers important advantages such as low cost, ease of application, and minimal side effects — characteristics that make it particularly attractive for both developed countries and those with limited resources. For healthcare professionals, these data provide a solid scientific basis for considering the integration of electroacupuncture into emergency protocols for patients with acute stroke.

However, it is essential to recognize the limitations of this study for an appropriate interpretation of the results. First, the research was conducted exclusively in animal models, and we know that benefits observed in mice do not always translate directly to humans because of physiological differences between species. Second, electroacupuncture proved effective only in moderate-intensity strokes, showing no benefits in more severe cases, suggesting that there is a specific therapeutic window for its application. Third, the study evaluated only short-term effects; additional research is needed to understand long-term benefits.

In addition, it will be crucial to determine precisely the maximum time after stroke onset during which electroacupuncture can still be effective — essential information for its practical clinical application. Future studies in humans are needed to confirm these promising findings and establish safe and effective treatment protocols, taking into account the particularities of different types of stroke and patient populations.