Biomaterial Database

Inhibition of potassium currents by the antiarrhythmic drug E4031 in rat taste receptor cells. 1996

X D Sun, and M S Herness

Indiana University School of Medicine, Center for Medical Education, Ball State University, Muncie 47306, USA.

The effect of the class III antiarrhythmic agent E4031 was investigated on a non-cardiac preparation as a potential tool for studying potassium currents. Patch clamp recordings in the whole cell configuration were performed on dissociated rat taste cells. These cells possess a variety of potassium currents; they also conduct action potentials. Unlike its more specific action on a type of delayed rectifier channel in cardiac cells, three types of potassium currents were reversibly diminished in taste cells in the presence of E4031. These included transient, sustained, and inwardly-rectifying potassium currents. Activation properties were not altered but the inactivation curve was shifted to the left by approximately 10 mV. Inhibitions of whole cell currents were voltage-dependent, larger at depolarized potentials, but were never complete. E4031 significantly broadened the gustatory action potential and, at higher concentrations, inhibited spike height, suggesting an additional inhibitory effect on sodium channels that was evident in voltage-clamp records. We conclude that E4031 is an effective inhibitor of potassium currents in the micromolar range and that it likely acts at a conserved segment of the potassium channel.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010880	Piperidines	A family of hexahydropyridines.
D011725	Pyridines	Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.
D005260	Female		Females
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
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
D000889	Anti-Arrhythmia Agents	Agents used for the treatment or prevention of cardiac arrhythmias. They may affect the polarization-repolarization phase of the action potential, its excitability or refractoriness, or impulse conduction or membrane responsiveness within cardiac fibers. Anti-arrhythmia agents are often classed into four main groups according to their mechanism of action: sodium channel blockade, beta-adrenergic blockade, repolarization prolongation, or calcium channel blockade.	Anti-Arrhythmia Agent,Anti-Arrhythmia Drug,Anti-Arrhythmic,Antiarrhythmia Agent,Antiarrhythmia Drug,Antiarrhythmic Drug,Antifibrillatory Agent,Antifibrillatory Agents,Cardiac Depressant,Cardiac Depressants,Myocardial Depressant,Myocardial Depressants,Anti-Arrhythmia Drugs,Anti-Arrhythmics,Antiarrhythmia Agents,Antiarrhythmia Drugs,Antiarrhythmic Drugs,Agent, Anti-Arrhythmia,Agent, Antiarrhythmia,Agent, Antifibrillatory,Agents, Anti-Arrhythmia,Agents, Antiarrhythmia,Agents, Antifibrillatory,Anti Arrhythmia Agent,Anti Arrhythmia Agents,Anti Arrhythmia Drug,Anti Arrhythmia Drugs,Anti Arrhythmic,Anti Arrhythmics,Depressant, Cardiac,Depressant, Myocardial,Depressants, Cardiac,Depressants, Myocardial,Drug, Anti-Arrhythmia,Drug, Antiarrhythmia,Drug, Antiarrhythmic,Drugs, Anti-Arrhythmia,Drugs, Antiarrhythmia,Drugs, Antiarrhythmic
D013649	Taste	The ability to detect chemicals through gustatory receptors in the mouth, including those on the TONGUE; the PALATE; the PHARYNX; and the EPIGLOTTIS.	Gustation,Taste Sense,Gustations,Sense, Taste,Senses, Taste,Taste Senses,Tastes
D013650	Taste Buds	Small sensory organs which contain gustatory receptor cells, basal cells, and supporting cells. Taste buds in humans are found in the epithelia of the tongue, palate, and pharynx. They are innervated by the CHORDA TYMPANI NERVE (a branch of the facial nerve) and the GLOSSOPHARYNGEAL NERVE.	Bud, Taste,Buds, Taste,Taste Bud
D015221	Potassium Channels	Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.	Ion Channels, Potassium,Ion Channel, Potassium,Potassium Channel,Potassium Ion Channels,Channel, Potassium,Channel, Potassium Ion,Channels, Potassium,Channels, Potassium Ion,Potassium Ion Channel