Galanin in somatosensory function.

Abstract

Galanin-like immunoreactivity and galanin receptors are found in dorsal root ganglion (DRG) cells and in dorsal horn interneurons, suggesting that this neuropeptide may have a role in sensory transmission and modulation at the spinal level. Expression of galanin or galanin receptors in the DRG and spinal cord are altered, sometimes in a dramatic fashion, by peripheral nerve injury or inflammation. Under normal conditions, galanin occurs in a small population of primary sensory neurons as well as in spinal interneurons. However, following peripheral nerve injury or inflammation, expression of galanin in primary afferents and spinal cord is upregulated. We examined the role of galanin in spinal processing of nociceptive information under normal and pathologic conditions in a large series of electrophysiologic and behavioral studies. Results suggest that under normal conditions galanin exerts tonic inhibition of nociceptive input to the central nervous system. After peripheral nerve injury the inhibitory control exerted by endogenous galanin, probably released from DRG neurons, is increased. During inflammation, galanin presumably released from dorsal horn interneurons also exerts an inhibitory function. Thus, stable galanin agonists may be useful in the treatment of inflammatory and neuropathic pain.

• Authors: Z Wiesenfeld-Hallin, X J Xu
• Journal: Annals of the New York Academy of Sciences (Ann N Y Acad Sci) Vol. 863 Pg. 383-9 (Dec 21 1998) ISSN: 0077-8923 [Print] United States
• PMID: 9928184 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Review)

Chemical References

• Receptors, Galanin
• Receptors, Neuropeptide
• Galanin

Topics

• Animals
• Galanin (physiology)
• Ganglia, Spinal (physiology)
• Humans
• Nervous System Physiological Phenomena
• Neurons, Afferent (physiology)
• Receptors, Galanin
• Receptors, Neuropeptide (physiology)
• Spinal Cord (physiology)