Calcium calmodulin-stimulated adenylyl cyclases contribute to activation of extracellular signal-regulated kinase in spinal dorsal horn neurons in adult rats and mice.

The extracellular signal-regulated kinase (Erk) cascades are suggested to contribute to excitatory synaptic plasticity in the CNS, including the spinal cord dorsal horn. However, many of their upstream signaling pathways remain to be investigated. Here, we demonstrate that glutamate and substance P (SP), two principal mediators of sensory information between primary afferent fibers and the spinal cord, activate Erk in dorsal horn neurons of both adult rat and mouse spinal cord.

Upregulation of forebrain NMDA NR2B receptors contributes to behavioral sensitization after inflammation.

Transgenic overexpression of NMDA NR2B receptors in forebrain regions increased behavioral responses to persistent inflammatory pain. However, it is not known whether inflammation leads to the upregulation of NR2B receptors in these regions. Here, we show that peripheral inflammation increased the expression of NMDA NR2B receptors and NR2B receptor-mediated synaptic currents in the anterior cingulate cortex (ACC).

A behavioral model of neuropathic pain induced by ligation of the common peroneal nerve in mice.

Unlabelled: Different laboratory animal models of neuropathic pain that replicate pathophysiological changes in patients have been developed. In most animal models of neuropathic pain, both sensory and motor nerves are injured. Thus, animals usually show both abnormal sensory and motor responses.