title: Activation of spinal ERK1/2 contributes to mechanical allodynia in a rat model of postoperative pain.
abstract: Extracellular signal‑regulated kinase (ERK) 1/2 in the spinal cord has been implicated in the development of neuropathic pain and inflammatory pain. However, a limited number of studies have investigated the role of spinal ERK in incisional pain. The present study aimed to determine the role of ERK in the spinal cord in incisional pain. Incisional pain was established in rats by a unilateral hind paw incision. ERK1/2 expression was analyzed by immunohistochemistry. Hypersensitivity to pain was evaluated by measuring the paw withdrawal threshold using the von Frey test. The mitogen‑activated protein kinase kinase (MEK) inhibitor, U0126, was administered 20 min prior to or 10 min following the incision by intrathecal or intraperitoneal injection. Phosphorylated ERK1/2 in the ipsilateral L4‑5 spinal superficial dorsal horn was activated 1 min following the incision, reached its peak level at 5 min and then returned to the basal level 20 min following the incision. Pretreatment, but not post‑treatment with U0126 markedly attenuated the pain hypersensitivity induced by the incision. Therefore, the present study indicates that the transient activation of spinal ERK1/2 contributes to the initiation of pain hypersensitivity following surgical incision.
authors: Department of Anesthesia, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, PR China.
authors: Xu-Dan
authors: XD
authors: Shi
authors: Di
authors: D
authors: Fu
authors: Jun-Mei
authors: JM
authors: Xu
authors: Yan-Ling
authors: YL
authors: Zhang
authors: Ru-Ping
authors: RP
authors: Dai
mesh_terms: D000818:Animals; D002070:Butadienes / Q000494:pharmacology; D004195:Disease Models, Animal; D004789:Enzyme Activation / Q000187:drug effects; D006930:Hyperalgesia / Q000150:complications / Q000201:enzymology* / Q000473:pathology; D006967:Hypersensitivity / Q000201:enzymology / Q000473:pathology; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D010149:Postoperative Pain / Q000150:complications / Q000201:enzymology* / Q000473:pathology; D010766:Phosphorylation / Q000187:drug effects; D020671:Posterior Horn Cells / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000187:drug effects / Q000473:pathology; D013116:Spinal Cord / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology
chemical_list: D002070:Butadienes; D009570:Nitriles; C113580:U 0126; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases