Biomaterial Database

Electrical responses to frog taste cells to chemical stimuli. 1976

N Akaike, and A Noma, and M Sato

1. Cells inside a fungiform papilla of the frog tongue were impaled with a glass capillary micro-electrode filled with 3 M-KCl. Cells considered to be taste cells showed a resting potential of about -35 mV and an input resistance of 17 Momega on the average. 2. Application of chemical stimuli such as salts, acids and quinine produced a sustained depolarization in a taste cell, the magnitude of depolarization being dependent on the stimulus concentration. Water and weak NaCl solution yielded a hyperpolarization. The thresholds for depolarization as well as the concentration-response relationships for various chemical stimuli in taste cells are in approximate agreement with those determined from the glossopharyngeal nerve responses. 3. The magnitude of depolarization produced by 0-1 M-NaCl and 0-03 M-CaCl2 was dependent on the membrane potential level and reduced linearly with a rise in the latter. However, depolarizations generated by 0-001 M-HDl and 0-02 M quinine changed little in magnitude by a membrane potential change over a wide range. 4. During depolarizations induced by NaCl and KCl a marked reduction in the input resistance of a cell was observed, the amount of the reduction depending on the stimulus concentration. The reduction was also produced by CaCl2 and HCl, but it is small compared with those by NaCl and KCl. Quinine produced an increase in the resistance associated with a depolarization. Water and weak NaCl solution produced an increase in the resistance associated with hyperpolarization. 5. The receptive mechanisms for various kinds of chemical stimuli are discussed in relation to changes in the membrane potential and the membrane conductance of taste cells.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008564	Membrane Potentials	The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).	Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
D011189	Potassium Chloride	A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.	Slow-K,Chloride, Potassium
D011803	Quinine	An alkaloid derived from the bark of the cinchona tree. It is used as an antimalarial drug, and is the active ingredient in extracts of the cinchona that have been used for that purpose since before 1633. Quinine is also a mild antipyretic and analgesic and has been used in common cold preparations for that purpose. It was used commonly and as a bitter and flavoring agent, and is still useful for the treatment of babesiosis. Quinine is also useful in some muscular disorders, especially nocturnal leg cramps and myotonia congenita, because of its direct effects on muscle membrane and sodium channels. The mechanisms of its antimalarial effects are not well understood.	Biquinate,Legatrim,Myoquin,Quinamm,Quinbisan,Quinbisul,Quindan,Quinimax,Quinine Bisulfate,Quinine Hydrochloride,Quinine Lafran,Quinine Sulfate,Quinine Sulphate,Quinine-Odan,Quinoctal,Quinson,Quinsul,Strema,Surquina,Bisulfate, Quinine,Hydrochloride, Quinine,Sulfate, Quinine,Sulphate, Quinine
D011892	Rana catesbeiana	A species of the family Ranidae (true frogs). The only anuran properly referred to by the common name "bullfrog", it is the largest native anuran in North America.	Bullfrog,Bullfrogs,Rana catesbeianas,catesbeiana, Rana
D002122	Calcium Chloride	A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.	Calcium Chloride Dihydrate,Calcium Chloride, Anhydrous
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
D006851	Hydrochloric Acid	A strong corrosive acid that is commonly used as a laboratory reagent. It is formed by dissolving hydrogen chloride in water. GASTRIC ACID is the hydrochloric acid component of GASTRIC JUICE.	Hydrogen Chloride,Muriatic Acid,Acid, Hydrochloric,Acid, Muriatic,Chloride, Hydrogen
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001001	Anura	An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.	Bombina,Frogs and Toads,Salientia,Toad, Fire-Bellied,Toads and Frogs,Anuras,Fire-Bellied Toad,Fire-Bellied Toads,Salientias,Toad, Fire Bellied,Toads, Fire-Bellied