Biomaterial Database

Tedisamil inactivates transient outward K+ current in rat ventricular myocytes. 1989

I D Dukes, and M Morad

Department of Physiology, University of Pennsylvania, Philadelphia 19104-6085.

The action of tedisamil, a new bradycardiac agent with antiarrhythmic properties, was investigated in single rat ventricular myocytes using the whole cell voltage-clamp technique. Under current clamp conditions, 1-20 microM tedisamil caused marked prolongations of the action potential. Over the same concentration range, in voltage-clamped myocytes, tedisamil suppressed the transient outward current (ito) and enhanced its inactivation in a dose-dependent manner. The half-maximal dose for the effect of tedisamil on ito was approximately 6 microM. Tedisamil had no significant effects on the inwardly rectifying potassium current and calcium current but did suppress the sodium current at concentrations greater than 20 microM. Our findings suggest that tedisamil represents a new type of antiarrhythmic agent that primarily suppresses the transient outward K+ current.

UI	MeSH Term	Description	Entries
D007425	Intracellular Membranes	Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.	Membranes, Intracellular,Intracellular Membrane,Membrane, Intracellular
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D001952	Bridged-Ring Compounds	Cyclic hydrocarbons that contain multiple rings which share one or more bridgehead connections.	Bridged Compounds,Bridged Ring Compounds
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002316	Cardiotonic Agents	Agents that have a strengthening effect on the heart or that can increase cardiac output. They may be CARDIAC GLYCOSIDES; SYMPATHOMIMETICS; or other drugs. They are used after MYOCARDIAL INFARCT; CARDIAC SURGICAL PROCEDURES; in SHOCK; or in congestive heart failure (HEART FAILURE).	Cardiac Stimulant,Cardiac Stimulants,Cardioprotective Agent,Cardioprotective Agents,Cardiotonic,Cardiotonic Agent,Cardiotonic Drug,Inotropic Agents, Positive Cardiac,Myocardial Stimulant,Myocardial Stimulants,Cardiotonic Drugs,Cardiotonics,Agent, Cardioprotective,Agent, Cardiotonic,Drug, Cardiotonic,Stimulant, Cardiac,Stimulant, Myocardial
D003521	Cyclopropanes	Three-carbon cycloparaffin cyclopropane (the structural formula (CH2)3) and its derivatives.
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
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.
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts