Capsaicin receptor immunoreactivity in the human trigeminal ganglion

Mingyan Hou, Rolf Uddman, Janos Tajti, Martin Kanje, Lars Edvinsson

Research output: Contribution to journalArticle

78 Citations (Scopus)

Abstract

The cloned capsaicin receptor, also known as vanilloid receptor subtype 1 (VR1) receptor, has been demonstrated to be an integral membrane protein with homology to a family of putative store-operated calcium channels. The VR1 receptor is activated not only by capsaicin but also by noxious heat and protons, and therefore it is suggested as a molecular integrator of chemical and physical stimuli that elicit pain. In the present study, indirect immunofluorescence detected a small number of neurons that are VR1 receptor immunoreactive (ir) (171 versus 1038 or 16% of all neuronal cell bodies) in the human trigeminal ganglion (TG). In addition, RT-PCR confirmed the presence of VR1 mRNA in the human TG. It has been hypothesized that TG neuronal cell bodies are the source of capsaicin-stimulated release of calcitonin gene-related peptide (CGRP), and hence co-localization experiments were performed. Around 10% of the VR1 receptor-ir is expressed on neurons that contain CGRP-ir (ten among 74) in the human TG, indicating that capsaicin may act through the VR1 receptor to modulate the release of CGRP and in turn to modulate pain. We observed that 8% of the VR1 receptor-ir neuronal cell bodies contain substance P-ir and 5% nitric oxide synthase. Capsaicin can release nitric oxide, CGRP and substance P from sensory nerves and contribute to central sensitization.

Original languageEnglish
Pages (from-to)223-226
Number of pages4
JournalNeuroscience Letters
Volume330
Issue number3
DOIs
Publication statusPublished - Sep 27 2002

Keywords

  • Calcitonin gene-related peptide
  • Capsaicin receptor
  • Nitric oxide synthase
  • Substance P
  • Vanilloid receptor

ASJC Scopus subject areas

  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Capsaicin receptor immunoreactivity in the human trigeminal ganglion'. Together they form a unique fingerprint.

  • Cite this