Neurokinin-1 receptor in peripheral nerve terminals mediates thermal hyperalgesia.

Abstract

Neurokinin-1 receptor (NK-1) plays an important role in nociception. The present study was to explore whether activation of peripheral NK-1 receptor, especially expressed on primary sensory afferents, could induce hyperalgesia and sensitize C-type sensory afferents. (1) Intraplantar administration of NK-1 agonist [Sar9, Met(O2)11]SP (Sar-SP, 0.2, 1 nmol, 20 microl) produced significant thermal hyperalgesia and edema, which was blocked by co-injection of NK-1 antagonist WIN51,708 (10 nmol). But in the rats with compound 48/80 treatment for mast cell depletion, the Sar-SP-induced edema, but not hyperalgesia, was attenuated. (2) Close-arterial injection of Sar-SP (1 nmol, 0.1 ml) excited and sensitized sensory C afferents of the sural nerve to heat stimuli. The results suggest involvement of NK-1 receptors expressed on the peripheral afferent terminals in thermal hyperalgesia mediated by directly sensitizing C-type sensory afferents.

• Authors: Wen-Ling Chen, Yu-Qiu Zhang, Zhi-Qi Zhao
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 339 Issue 1 Pg. 132-6 (Jan 06 2006) ISSN: 0006-291X [Print] United States
• PMID: 16300741 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Androstanes
• Benzimidazoles
• Neurokinin-1 Receptor Antagonists
• Receptors, Neurokinin-1
• WIN 51708
• substance P, Sar(9)-Met(O2)(11)-
• Substance P
• p-Methoxy-N-methylphenethylamine

Topics

• Androstanes (pharmacology)
• Animals
• Behavior, Animal
• Benzimidazoles (pharmacology)
• Cell Degranulation (drug effects)
• Edema (metabolism, physiopathology)
• Hyperalgesia (metabolism)
• Male
• Mast Cells (drug effects, physiology)
• Nerve Endings (metabolism)
• Neurokinin-1 Receptor Antagonists
• Neurons, Afferent (metabolism)
• Rats
• Rats, Sprague-Dawley
• Receptors, Neurokinin-1 (agonists, physiology)
• Substance P (analogs & derivatives, pharmacology, physiology)
• Sural Nerve (drug effects, metabolism)
• p-Methoxy-N-methylphenethylamine (pharmacology)