{'fraction_non_alphanumeric': 0.03843689942344651, 'fraction_numerical': 0.017937219730941704, 'mean_word_length': 5.973214285714286, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Butter flavoring‐elicited relaxation and bioelectric responses of rat airway are independent of bitter taste receptors (TAS2R) (660.14)

“Popcorn workers’ lung” is a fixed obstructive pulmonary disease caused by inhalation of artificial butter flavoring vapor. In the isolated, perfused rat trachea preparation, the butter flavorings, diacetyl and 2,3‐pentanedione elicit airway smooth muscle (ASM) relaxation. TAS2Rs mediate relaxation of ASM by increasing the concentration of intracellular Ca2+ via large‐conductance Ca2+‐activated K+ (BKCa) channels. This study investigated the potential involvement of TAS2Rs in relaxant responses of tracheal ASM and bioelectric responses of tracheal epithelial cells in response to denatonium (1 mM), a TAS2R agonist, diacetyl (3 mM) and 2,3‐pentanedione (3 mM). In rat tracheal strips contracted with methacholine (3×10−5 M), denatonium‐induced relaxation responses were inhibited by iberiotoxin (IbTx; 100 nM), a BKCa channel blocker, suggesting that denatonium‐induced relaxation is mediated by TAS2R. However, relaxation responses to the butter flavorings were not antagonized by IbTx. Whether TAS2R mediate bioelectric responses to denatonium and flavorings in the epithelium was investigated. The decrease in short‐circuit current (Isc) in response to denatonium and flavorings were not blocked by apical IbTx, suggesting that the responses in the epithelium were not mediated by TAS2R. Our findings indicate that BKCa channels are not involved in flavoring‐induced bronchodilation or Isc responses in rat airways.