Biomaterial Database

Three potassium currents in mouse motor nerve terminals. 1989

N Tabti, and C Bourret, and A Mallart

Unité de Physiologie Neuromusculaire, Laboratoire de Neurobiologie Cellulaire et Moléculaire, C.N.R.S., Gif sur Yvette, France.

A study of the K conductance of the presynaptic membrane has been performed in the triangularis sterni muscle of the mouse. External currents generated in the presynaptic terminals upon invasion by action potentials have been recorded using microelectrodes inserted into the perineurium of preterminal nerve bundles. The voltage-dependent K current could be pharmacologically dissected into fast (IKf) and slow (IKs) components. While both are sensitive to 3,4-diaminopyridine (3,4-DAP), only IKf is sensitive to tetraethylammonium (TEA). Uranyl (100-200 microM) and guanidine (5-10 mM) produced a near complete block of IKf and IKs, which can explain their facilitatory effect upon transmitter release. The third K current of presynaptic terminals is Ca2+-dependent, but was activated also by Sr2+. This current could be suppressed by nanomolar doses of charybdotoxin; it is also sensitive to TEA but not to 3,4-DAP, uranyl or guanidine.

UI	MeSH Term	Description	Entries
D009469	Neuromuscular Junction	The synapse between a neuron and a muscle.	Myoneural Junction,Nerve-Muscle Preparation,Junction, Myoneural,Junction, Neuromuscular,Junctions, Myoneural,Junctions, Neuromuscular,Myoneural Junctions,Nerve Muscle Preparation,Nerve-Muscle Preparations,Neuromuscular Junctions,Preparation, Nerve-Muscle,Preparations, Nerve-Muscle
D009942	Organometallic Compounds	A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)	Metallo-Organic Compound,Metallo-Organic Compounds,Metalloorganic Compound,Organometallic Compound,Metalloorganic Compounds,Compound, Metallo-Organic,Compound, Metalloorganic,Compound, Organometallic,Compounds, Metallo-Organic,Compounds, Metalloorganic,Compounds, Organometallic,Metallo Organic Compound,Metallo Organic Compounds
D006146	Guanidines	A family of iminourea derivatives. The parent compound has been isolated from mushrooms, corn germ, rice hulls, mussels, earthworms, and turnip juice. Derivatives may have antiviral and antifungal properties.
D000077770	Amifampridine	4-Aminopyridine derivative that acts as a POTASSIUM CHANNEL blocker to increase release of ACETYLCHOLINE from nerve terminals. It is used in the treatment of CONGENITAL MYASTHENIC SYNDROMES.	Ruzurgi,3,4-Diaminopyridine,Amifampridine Phosphate,Firdapse,3,4 Diaminopyridine
D000631	Aminopyridines	Pyridines substituted in any position with an amino group. May be hydrogenated but must retain at least one double bond.	Aminopyridine
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
D013757	Tetraethylammonium Compounds	Quaternary ammonium compounds that consist of an ammonium cation where the central nitrogen atom is bonded to four ethyl groups.	Tetramon,Tetrylammonium,Compounds, Tetraethylammonium
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
D015761	4-Aminopyridine	One of the POTASSIUM CHANNEL BLOCKERS with secondary effect on calcium currents which is used mainly as a research tool and to characterize channel subtypes.	4-Aminopyridine Sustained Release,Dalfampridine,Fampridine-SR,Pymadine,VMI-103,4 Aminopyridine,4 Aminopyridine Sustained Release,Fampridine SR,Sustained Release, 4-Aminopyridine,VMI 103,VMI103
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus