Table of Contents
Journal of Signal Transduction
Volume 2011, Article ID 468061, 10 pages
Review Article

Activation of Mitogen-Activated Protein Kinase in Descending Pain Modulatory System

1Department of Physiology, Wakayama Medical University, Kimiidera 811-1, Wakayama City 641-8509, Japan
2Department of Anatomy and Neurobiology, Wakayama Medical University, Kimiidera 811-1, Wakayama City 641-8509, Japan

Received 8 August 2010; Accepted 14 October 2010

Academic Editor: Kohsuke Takeda

Copyright © 2011 Hiroki Imbe 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.


The descending pain modulatory system is thought to undergo plastic changes following peripheral tissue injury and exerts bidirectional (facilitatory and inhibitory) influence on spinal nociceptive transmission. The mitogen-activated protein kinases (MAPKs) superfamily consists of four main members: the extracellular signal-regulated protein kinase1/2 (ERK1/2), the c-Jun N-terminal kinases (JNKs), the p38 MAPKs, and the ERK5. MAPKs not only regulate cell proliferation and survival but also play important roles in synaptic plasticity and memory formation. Recently, many studies have demonstrated that noxious stimuli activate MAPKs in several brain regions that are components of descending pain modulatory system. They are involved in pain perception and pain-related emotional responses. In addition, psychophysical stress also activates MAPKs in these brain structures. Greater appreciation of the convergence of mechanisms between noxious stimuli- and psychological stress-induced neuroplasticity is likely to lead to the identification of novel targets for a variety of pain syndromes.