Amiloride-Sensitive and Amiloride-Insensitive Responses to NaCl + Acid Mixtures in Hamster Chorda Tympani Nerve
Autor: | Bradley K. Formaker, Lawrence Savoy, Thomas P. Hettinger, Marion E. Frank |
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Jazyk: | angličtina |
Rok vydání: | 2012 |
Předmět: |
Taste
Sucrose Physiology Sodium chemistry.chemical_element Hamster Sodium Chloride Citric Acid Sodium Channels Amiloride Behavioral Neuroscience chemistry.chemical_compound Acetic acid Electrolytes Physiology (medical) Cricetinae None medicine Animals Acetic Acid biology Hydrogen-Ion Concentration biology.organism_classification Sensory Systems chemistry Biochemistry Biophysics Chorda Tympani Nerve Citric acid Mesocricetus medicine.drug |
Popis: | Component signaling in taste mixtures containing both beneficial and dangerous chemicals depends on peripheral processing. Unidirectional mixture suppression of chorda tympani (CT) nerve responses to sucrose by quinine and acid is documented for golden hamsters (Mesocricetus auratus). To investigate mixtures of NaCl and acids, we recorded multifiber responses to 50 mM NaCl, 1 and 3 mM citric acid and acetic acid, 250 μM citric acid, 20 mM acetic acid, and all binary combinations of each acid with NaCl (with and without 30 μM amiloride added). By blocking epithelial Na(+) channels, amiloride treatment separated amiloride-sensitive NaCl-specific responses from amiloride-insensitive electrolyte-generalist responses, which encompass all of the CT response to the acids as well as responses to NaCl. Like CT sucrose responses, the amiloride-sensitive NaCl responses were suppressed by as much as 50% by citric acid (P = 0.001). The amiloride-insensitive electrolyte-generalist responses to NaCl + acid mixtures approximated the sum of NaCl and acid component responses. Thus, although NaCl-specific responses to NaCl were weakened in NaCl-acid mixtures, electrolyte-generalist responses to acid and NaCl, which tastes KCl-like, were transmitted undiminished in intensity to the central nervous system. The 2 distinct CT pathways are consistent with known rodent behavioral discriminations. |
Databáze: | OpenAIRE |
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