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The Sciatic Nerve Cuffing Model of Neuropathic Pain in Mice
Published on: July 16, 2014
Pain modulation by nitric oxide in the spinal cord
Marco Aurélio M Freire1, Joanilson S Guimarães, Walace Gomes Leal
1Edmond and Lily Safra International Institute of Neuroscience of Natal (ELS-IINN) Natal, RN, Brazil.
Frontiers in Neuroscience
|December 17, 2009
Summary
Nitric oxide (NO), a molecule in the central nervous system, has dual roles in pain signaling. This review explores the complex involvement of NO in central pain sensitization and its impact on nociceptive circuits.
Area of Science:
- Neuroscience
- Molecular Biology
- Pain Research
Background:
- Nitric oxide (NO) acts as a key messenger molecule in the central nervous system (CNS).
- NO synthesis in the CNS is often initiated by N-methyl-D-aspartate (NMDA) receptor activation.
- The enzyme nitric oxide synthase (NOS) exists in three isoforms: neuronal (nNOS), endothelial (eNOS), and inducible (iNOS), each with distinct brain functions.
Purpose of the Study:
- To review the multifaceted role of nitric oxide (NO) in central pain sensitization.
- To elucidate the contribution of NO to nociceptive processing within the CNS.
Main Methods:
- Literature review of studies investigating nitric oxide synthase (NOS) and its isoforms in the central nervous system (CNS).
- Analysis of research on the modulation of synaptic transmission and long-term potentiation by NO.
- Examination of NO's involvement in spinal cord nociceptive circuits.
Main Results:
- Neuronal nitric oxide synthase (nNOS) plays a significant role in modulating synaptic transmission, including long-term potentiation.
- NO exhibits both beneficial and detrimental effects in the CNS, presenting a 'Janus face' in its functions.
- Specific isoforms of NOS are implicated in distinct neurobiological events within the brain.
Conclusions:
- Nitric oxide (NO) is critically involved in the mechanisms underlying central pain sensitization.
- Understanding NO's role in nociceptive circuits is essential for comprehending pain modulation in the CNS.
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