Table of Contents
ISRN Pain
Volume 2013, Article ID 340167, 5 pages
http://dx.doi.org/10.1155/2013/340167
Research Article

Distribution of Spinal Sensitization Evoked by Inflammatory Pain Using Local Spinal Cord Glucose Utilization Combined with 3H-Phorbol 12,13-Dibutyrate Binding in Rats

1Division of Neurosciences and Department of Laboratory Sciences, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan
22nd Department of Anatomy, Sapporo Medical University, 17-Nishi Minami-1, Chuo-ku, Sapporo 060-8556, Japan
3Department of Dental Anesthesiology, Kyushu Dental University, 3-1-6 Manazuru, Kokura, Kita-kyusyu 803-0001, Japan
4Department of Anesthesiology, Pusan National University, 9 Bugok 3-dong, Geumjeong-gu, Busan 609-757, Republic of Korea

Received 29 September 2013; Accepted 10 November 2013

Academic Editors: V. De Novellis, J. Ferreira, and Y.-R. Wen

Copyright © 2013 Yasuda Seiko et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Aims. Hyperalgesia following tissue injury is induced by plasticity in neurotransmission. Few investigators have considered the ascending input which activates the superficial of spinal cord. The aim was to examine neurotransmission and nociceptive processing in the spinal cord after mustard-oil (MO) injection. Both in vitro and in vivo autoradiographs were employed for neuronal activity and transmission in discrete spinal cord regions using the 14C-2-deoxyglucose method and 3H-phorbol 12,13-dibutyrate (3H-PDBu) binding sites. Methods. To quantify the hyperalgesia evoked by MO, the flinching was counted for 60 min after MO (20%, 50 μL) injection in Wistar rats. Simultaneous determination of 14C-2-deoxyglucose and 3H-PDBu binding was used for a direct observation of neuronal/metabolic changes and intracellular signaling in the spinal cord. Results. MO injection evoked an increase in flinching for 60 min. LSCGU significantly increased in the Rexed I-II with 3H-PDBu binding in the ipsilateral side of spinal cord. Discussion. We clearly demonstrated that the hyperalgesia is primarily relevant to increased neuronal activation with PKC activation in the Rexed I-II of the spinal cord. In addition, functional changes such as “neuronal plasticity” may result in increased neuronal excitability and a central sensitization.