In a Perspectives paper published in Neural Regeneration Research (Vol. 9, No. 14), Professor Peter Drummond speculates about neuronal changes that might contribute to chronic pain after peripheral nerve injury.
Professor Drummond and co-workers at Murdoch University, Perth Western Australia, discovered recently that the expression of α1-adrenoceptors increases on pain-signalling nerve fibers that survive peripheral injury.
As these receptors boost neural excitability, an increase in their expression could intensify pain.
After tissue injury, resident cells and other cells that migrate to the site of injury release a cocktail of inflammatory mediators and growth factors that help to prevent infection and instigate tissue repair.
However, these mediators may also trigger the up-regulation of α1-adrenoceptors on resident cells and nerve fibers that survive the injury.
As certain resident and migratory cells are a major source of inflammatory mediators and growth factors, the up-regulation of α1-adrenoceptors may promote a cycle of chronic inflammation and pain. If so, blocking the alpha-1-adrenoceptor might prove to be a useful therapeutic strategy for patients with an adrenergic component of pain after peripheral nerve injury.
Article: "Neuronal changes resulting in up-regulation of alpha-1 adrenoceptors after peripheral nerve injury" by Peter D. Drummond (Centre for Research on Chronic Pain and Inflammatory Diseases, Murdoch University, Perth, Western Australia, Australia).
Drummond PD. Neuronal changes resulting in up-regulation of alpha-1 adrenoceptors after peripheral nerve injury. Neural Regen Res. 2014;9(14):1337-1340.