Contribution of proton transporter to acid-induced receptor potential in frog taste cells.
1. The generative mechanism of the acid-induced receptor potential in frog taste cells was re-examined with micro-electrodes. 2. The amplitude of receptor potentials in a taste cell induced by 1 mM acetic acid increased as the concentration of Ca2+, Sr2+ and Ba2+ on the tongue surface was increased. 3. The amplitude of the acid-induced receptor potential was inhibited by about 40% by a proton pump blocker DCCD (N,N'-dicyclohexylcarbodiimide) added to superficial normal saline. 4. It is concluded that most of the acid-induced response in a frog taste cell was generated by current carried through proton-gated Ca2+ channel of the apical receptive membrane. The remaining part of the acid response was generated by current carried through a DCCD-sensitive proton transporter of the receptive membrane.
Okada
Y
Y
Department of Physiology, Nagasaki University School of Dentistry, Japan.
Miyamoto
T
T
Sato
T
T
D000818:Animals; D001692:Biological Transport; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007473:Ion Channels / Q000378:metabolism; D017494:Proton Pumps; D011892:Rana catesbeiana; D011984:Sensory Receptor Cells / Q000187:drug effects / Q000502:physiology*; D013649:Taste
D007473:Ion Channels; D017494:Proton Pumps; D004024:Dicyclohexylcarbodiimide