title: Spinal changes of a newly isolated neuropeptide endomorphin-2 concomitant with vincristine-induced allodynia.
abstract: Chemotherapy-induced neuropathic pain (CNP) is the major dose-limiting factor in cancer chemotherapy. However, the neural mechanisms underlying CNP remain unclear. There is increasing evidence implicating the involvement of spinal endomorphin-2 (EM2) in neuropathic pain. In this study, we used a vincristine-evoked rat CNP model displaying mechanical allodynia and central sensitization, and observed a significant decrease in the expression of spinal EM2 in CNP. Also, while intrathecal administration of exogenous EM2 attenuated allodynia and central sensitization, the mu-opioid receptor antagonist β-funaltrexamine facilitated these events. We found that the reduction in spinal EM2 was mediated by increased activity of dipeptidylpeptidase IV, possibly as a consequence of chemotherapy-induced oxidative stress. Taken together, our findings suggest that a decrease in spinal EM2 expression causes the loss of endogenous analgesia and leads to enhanced pain sensation in CNP.
authors.affiliation: Department of Neurosurgery, The Zhumadian City Center Hospital, Zhumadian, P.R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of ICU, The Zhumadian City Center Hospital, Zhumadian, P.R. China.
authors.forename: Yong-Gang
authors.initials: YG
authors.lastname: Zhang
authors.affiliation: Department of Burn, The 159th Hospital of PLA, Zhumadian, P.R. China.
authors.forename: Guo-An
authors.initials: GA
authors.lastname: Lin
authors.affiliation: Department of Pain, The Zhumadian City Center Hospital, Zhumadian, P.R. China.
authors.forename: He-Qiu
authors.initials: HQ
authors.lastname: Xie
authors.affiliation: School of Statistics, Xi'an University of Finance and Economics, Xi'an, P.R. China.
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Pan
authors.affiliation: Department of Oncology, The 159th Hospital of PLA, Zhumadian, P.R. China.
authors.forename: Ben-Qing
authors.initials: BQ
authors.lastname: Huang
authors.affiliation: Department of Neurosurgery, The Zhumadian City Center Hospital, Zhumadian, P.R. China.
authors.forename: Ji-Dong
authors.initials: JD
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, The Zhumadian City Center Hospital, Zhumadian, P.R. China.
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of student affairs, Xinxiang Medical University, Xinxiang, P.R. China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, The Zhumadian City Center Hospital, Zhumadian, P.R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, The Zhumadian City Center Hospital, Zhumadian, P.R. China.
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Chen
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000633:toxicity; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000378:metabolism; D004594:Electrophysiology; D005455:Fluorescent Antibody Technique; D006930:Hyperalgesia / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D007278:Injections, Spinal; D008297:Male; D009437:Neuralgia / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology; D009842:Oligopeptides / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D013116:Spinal Cord / Q000187:drug effects / Q000378:metabolism*; D014750:Vincristine / Q000633:toxicity*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D009842:Oligopeptides; D017382:Reactive Oxygen Species; C105294:endomorphin 2; D014750:Vincristine; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases