Taste transduction mechanism: similar effects of various modifications of gustatory receptors on neural responses to chemical and electrical stimulation in the frog
Responses in the frog glossopharyngeal nerve induced by electrical stimulation of the tongue were compared with those induced by chemical stimuli under various conditions. (a) Anodal stimulation induced much larger responses than cathodal stimulation, and anodal stimulation of the tongue adapted to 5 mM MgCl2 produced much larger responses than stimulation with the tongue adapted to 10 mM NaCl at equal current intensities, as chemical stimulation with MgCl2 produced much larger responses than stimulation with NaCl at equal concentration. (b) The enhansive and suppressive effects of 8-anilino-1-naphthalenesulfonate, NiCl2, and uranyl acetate on the responses to anodal current were similar to those on the responses to chemical stimulation. (c) Anodal stimulation of the tongue adapted to 50 mM CaCl2 resulted in a large response, whereas application of 1 M CaCl2 to the tongue adapted to 50 mM CaCl2 produced only a small response. This, together with theoretical considerations, suggested that the accumulation of salts on the tongue surface is not the cause of the generation of the response to anodal current. (d) Cathodal current suppressed the responses induced by 1 mM CaCl2, 0.3 M ethanol, and distilled water. (e) The addition of EGTA or Ca-channel blockers (CdCl2 and verapamil) to the perfusing solution of the lingual artery reversibly suppressed both the responses to chemical stimulus (NaCl) and to anodal current with 10 mM NaCl. (f) We assume from the results obtained that electrical current from the microvillus membrane of a taste cell to the synaptic area supplied by anodal stimulation or induced by chemical stimulation activates the voltage-dependent Ca channel at the synaptic area.
- Research Organization:
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
- OSTI ID:
- 5501436
- Journal Information:
- J. Gen. Physiol.; (United States), Vol. 78:3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Raman spectroscopic studies of chemical speciation in calcium chloride melts
Taste responses to deuterium oxide
Related Subjects
NERVES
STIMULATION
SALTS
BIOLOGICAL ACCUMULATION
TASTE BUDS
CHEMICAL ACTIVATION
CALCIUM CHLORIDES
ELECTRIC CURRENTS
FROGS
MAGNESIUM CHLORIDES
NICKEL CHLORIDES
RECEPTORS
SODIUM CHLORIDES
SULFONATES
TONGUE
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
AMPHIBIANS
ANIMALS
AQUATIC ORGANISMS
BODY
CALCIUM COMPOUNDS
CALCIUM HALIDES
CHLORIDES
CHLORINE COMPOUNDS
CURRENTS
DIGESTIVE SYSTEM
HALIDES
HALOGEN COMPOUNDS
MAGNESIUM COMPOUNDS
NERVOUS SYSTEM
NICKEL COMPOUNDS
ORAL CAVITY
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANS
SENSE ORGANS
SODIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
VERTEBRATES
551000* - Physiological Systems