Upregulation of α1-adrenoceptors on cutaneous nerve fibres after partial sciatic nerve ligation and in complex regional pain syndrome type II.

Autor:	Drummond PD; Centre for Research on Chronic Pain and Inflammatory Diseases, Murdoch University, Perth, Western Australia, Australia Pain Management Research Institute, Kolling Institute, Northern Clinical School, The University of Sydney, NSW, Australia Australian School of Advanced Medicine, Macquarie University, Sydney, NSW, Australia., Drummond ES, Dawson LF, Mitchell V, Finch PM, Vaughan CW, Phillips JK
Jazyk:	angličtina
Zdroj:	Pain [Pain] 2014 Mar; Vol. 155 (3), pp. 606-616. Date of Electronic Publication: 2013 Dec 14.
DOI:	10.1016/j.pain.2013.12.021
Abstrakt:	After peripheral nerve injury, nociceptive afferents acquire an abnormal excitability to adrenergic agents, possibly due to an enhanced expression of α1-adrenoceptors (α1-ARs) on these nerve fibres. To investigate this in the present study, changes in α1-AR expression on nerve fibres in the skin and sciatic nerve trunk were assessed using immunohistochemistry in an animal model of neuropathic pain involving partial ligation of the sciatic nerve. In addition, α1-AR expression on nerve fibres was examined in painful and unaffected skin of patients who developed complex regional pain syndrome (CRPS) after a peripheral nerve injury (CRPS type II). Four days after partial ligation of the sciatic nerve, α1-AR expression was greater on dermal nerve fibres that survived the injury than on dermal nerve fibres after sham surgery. This heightened α1-AR expression was observed on nonpeptidergic nociceptive afferents in the injured sciatic nerve, dermal nerve bundles, and the papillary dermis. Heightened expression of α1-AR in dermal nerve bundles after peripheral nerve injury also colocalized with neurofilament 200, a marker of myelinated nerve fibres. In each patient examined, α1-AR expression was greater on nerve fibres in skin affected by CRPS than in unaffected skin from the same patient or from pain-free controls. Together, these findings provide compelling evidence for an upregulation of α1-ARs on cutaneous nociceptive afferents after peripheral nerve injury. Activation of these receptors by circulating or locally secreted catecholamines might contribute to chronic pain in CRPS type II. (Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu