Electrophysiological characteristics of IB4-negative TRPV1-expressing muscle afferent DRG neurons

• Lin Yi-Wen

  College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University Research Center for Chinese Medicine & Acupuncture, China Medical University

• Chen Chih-Cheng

  Institute of Biomedical Sciences, Academia Sinica Taiwan Mouse Clinic, Academia Sinica

抄録

Muscle afferent neurons that express transient receptor potential vanilloid type I (TRPV1) are responsible for muscle pain associated with tissue acidosis. We have previously found that TRPV1 of isolectin B4 (IB4)-negative muscle nociceptors plays an important role in the acid-induced hyperalgesic priming and the development of chronic hyperalgesia in a mouse model of fibromyalgia. To understand the electrophysiological properties of the TRPV1-expressing muscle afferent neurons, we used whole-cell patch clamp recording to study the acid responsiveness and action potential (AP) configuration of capsaicin-sensitive neurons innervating to gastrocnemius muscle. Here we showed that IB4-negative TRPV1-expressing muscle afferent neurons are heterogeneous in terms of cell size, resting membrane potential, AP configuration, tetrodotoxin (TTX)-resistance, and acid-induced current (I_acid), as well as capsaicin-induced current (I_cap). TRPV1-expressing neurons were all acid-sensitive and could be divided into two acidsensitive groups depending on an acid-induced sustained current (type I) or an acid-induced biphasic ASIC3-like current (type II). Type I TRPV1-expressing neurons were distinguishable from type II TRPV1-expressing neurons in AP overshoot, afterhyperpolarization duration, and all I_acid parameters, but not in AP threshold, TTX-resistance, resting membrane potential, and I_cap parameters. These differential biophysical properties of TRPV1-expressing neurons might partially annotate their different roles involved in the development and maintenance of chronic muscle pain.

収録刊行物

• BIOPHYSICS

  BIOPHYSICS 11 (0), 9-16, 2015

  日本生物物理学会

キーワード

• action potential
• ASIC3
• capsaicin
• muscle pain
• TTX

詳細情報

• CRID: 1390001205222017024
• NII論文ID: 130004940806
• DOI: 10.2142/biophysics.11.9
• ISSN: 13492942
• Web Site: https://www.jstage.jst.go.jp/article/biophysics/11/0/11_9/_pdf
• 本文言語コード: en
• データソース種別:
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  • Crossref
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