Pain Hypersensitivity and Chronic Pain Syndromes

Pain systems need to be sensitive enough to detect potentially harmful stimuli.  But often they become too sensitive, causing pain from stimuli that are not harmful.  The mechanisms of this sensitization are beginning to be understood.  Pain hypersensitivity takes two forms:

  • Thresholds are lowered so that stimuli that would normally not produce pain now do so (allodynia).
  • Responsiveness is increased, so that noxious stimuli produce an exaggerated and prolonged pain (hyperalgesia).

Pain hypersensitivity after an injury ensures that contact with the injured tissue is minimized until repair is complete is an adaptive response.  However, pain hypersensitivity may persist long after an injury has healed or occur in the absence of any injury.  In this case, pain provides no protective benefit, and is a manifestation of pathological change in the nervous system.  Two mechanisms that produce pain hypersensitivity are involved: peripheral and central sensitization.  “Sensitization” indicates an increase in the excitability of neurons, which become more sensitive to sensory input. (1)

Some chronic pain syndromes may in fact result from pain hypersensitivity and often multiple treatment modalities are needed to garner relief. Although its exact mechanism of action is unknown, the Prezacor compound found in the Energeze Patch is theorized to modify the spontaneous firing frequency of the C-fiber nociceptors that have become more sensitive in chronic pain syndromes.  Given the electro-dynamic properties of the Prezacor compound, it may be absorbing a small amount of negatively charged energy associated with the surface of the body and re-emitting a lower energy charge that has an effect on the cell membranes thereby modifying the firing of nerve pain fibers.

It is expected that voltage can affect large molecules embedded in a cell membrane and it is possible that an external electric field might cause an effect if it creates changes bigger than the natural thermal noise in a membrane.  If the large molecules in cell membranes being affected are enzymes, it may be possible for external fields to produce changes in some biochemical reactions.  These, in turn, might affect wider processes within the cell.  Researchers have found that the smallest applied electric field to which large molecules in cell membranes may respond is about two-thousandths of a volt per inch.  In some circumstances, investigators calculate, fields even a thousand times lower may be able to cause effects. (2,3)

  1. Baron R. 2006. Mechanisms of disease: neuropathic pain—a clinical perspective. Nat Clin. Pract. Neurol. 2(2):95-106.
  2. Weaver JC, Astumian RD.  1990. The response of living cells to very weak electric fields: the thermal noise limit. Science 247(4941):459-462.
  3. Antov Y, Barbul A, Mantsur H, Korenstein R. 2005. Electroendocytosis: exposure of cells to pulsed low electric fields enhances adsorption and uptake of macromolecules. Biophys J. 88(3):2206–2223.