Electroacupucture and nerve growth factor: potential clinical applications.

The nerve growth factor (NGF) is a neurotrophin regulating the survival and function peripheral sensory and sympathetic neurons and of forebrain cholinergic neurons. Both peripheral neuropathies and brain cholinergic dysfunctions could benefit from NGFbased therapies, but the clinical use of NGF has been so far hampered by the development of important side effects, like hyperalgesia and autonomic dysfunctions. Acupuncture is a therapeutic technique and is a part of traditional Chinese medicine. Western descriptions of the clinical efficacy of acupuncture on pain, inflammation, motor dysfunction, mood disorders, and seizures are based on the stimulation of several classes of sensory afferent fibers and the consequent activation of physiological processes similar to those resulting from physical exercise or deep massage. Recently, it has been shown that peripheral sensory stimulation by electroacupuncture (EA) could improve brain NGF availability and utilization, at the same time counteracting the major sideeffects induced by NGF administration. This review focuses on the emerging links between EA and NGF with special emphasis on the work carried out in the last decade in our laboratory, investigating the role of NGF as a mediator of EA effects in the central nervous system and as a modulator of sensory and autonomic activity.