Glycine Inhibitory Dysfunction Induces a Selectively Dynamic, Morphine-Resistant, and Neurokinin 1 Receptor- Independent Mechanical Allodynia

• DOI: 10.1523/jneurosci.3923-08.2009
• Publication Date: 2009-02-25T18:34:19Z
• Authors: Loïs S. Miraucourt; Xavier Moisset; Radhouane Dallel; Daniel L. Voisin
• Keywords: Disinhibition; Allodynia

Dynamic mechanical allodynia is a widespread and intractable symptom of neuropathic pain for which there lack effective therapy. We recently provided novel perspective on the mechanisms this by showing that simple switch in trigeminal glycine synaptic inhibition can turn touch into unmasking innocuous input to superficial dorsal horn nociceptive specific neurons through local excitatory, NMDA-dependent neural circuit involving expressing gamma isoform protein kinase C. Here, we further investigated clinical relevance processing disinhibition. First, showed disinhibition with strychnine selectively induced dynamic but not static allodynia. The was resistant morphine. Second, morphine did prevent activation underlying as shown study Fos expression extracellular-signal regulated phosphorylation neurons. Third, contrast intradermal capsaicin injections, light, stimuli applied under produce neurokinin 1 (NK1) receptor internalization Finally, only express NK1 receptor. To summarize, selectivity resistance glycine-disinhibition paradigm adequately reflect characteristics present findings thus reveal involvement selective allodynia, operates lamina nociceptive-specific do bear provide an explanation differences pharmacological sensitivity symptoms.