| Autor: |
Kojun Tsuji, Takanori Tsujimura, Shogo Sakai, Taku Suzuki, Midori Yoshihara, Kouta Nagoya, Jin Magara, Yoshihide Satoh, Makoto Inoue |
| Předmět: |
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| Zdroj: |
American Journal of Physiology: Gastrointestinal & Liver Physiology; Nov2020, Vol. 319 Issue 5, pG564-G572, 9p |
| Abstrakt: |
Capsaicin powerfully evokes the swallowing reflex and is a known therapeutic agent for improving dysphagia and preventing aspiration pneumonia. However, the role of capsaicin-sensitive nerves in the initiation of swallowing evoked by various natural stimuli remains unclear. To explore this question, we blocked laryngeal capsaicin-sensitive nerves following the coapplication of QX-314 and capsaicin (QX/Cap), and investigated the effects on swallowing evoked by mechanical and chemical stimulation in anesthetized rats. Swallows were evoked by capsaicin, carbonated water (CW), distilled water (DW), and punctate mechanical stimulation using von Frey filaments applied topically to the larynx. Swallows were documented by recording electromyographic activation of the suprahyoid and thyrohyoid muscles. The initiation of swallowing by capsaicin was strongly suppressed at 5 min following QX/Cap treatment and returned in a time-dependent manner. CWevoked swallows at 5 min following QX/Cap treatment were significantly diminished compared with before and 30 min after treatment. In contrast, DW-evoked and mechanically evoked swallows were unchanged by QX/Cap treatment. Furthermore, CW-evoked swallows were virtually abolished by transection of the superior laryngeal nerves and significantly decreased by the topical application of acidsensing ion channel-3 (ASIC3) inhibitor APETx2, but they were not affected by the nonselective transient receptor potential channel inhibitor ruthenium red or the ASIC1 inhibitor mambalgin-1. Taken together, we speculate that capsaicin-sensitive nerves play an important role in the initiation of CW-evoked swallows. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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