Biomaterial Database

Potassium induced potential changes in rat diaphragm muscle. 1976

A Den Hertog, and J J Mooij

The effect of different potassium concentrations on the membrane potential and membrane resistance of rat diaphragm muscle fibres was measured by means of a double sucrose gap method and a microelectrode technique. Concentration measurements showed that the muscle fibres gained sodium and lost potassium in the equilibration period. In the absence of external chloride changing the external potassium concentration from 2.8 mM to potassium-free caused a depolarization of the membrane of about 30 mV and a small increase in membrane resistance. This K-dependent potential change (K-response) was induced by ouabain, K-strophanthin, 2,4-dinitrophenol and cyanide, indicating that an energy requiring process is involved. The temperature dependence of the K-response found is consistent with this assumption. Variation in potassium permeability in the absence and presence of external potassium could account for only 13% of the K-response. The K-response amplitude appeared to depend on the external potassium and the internal sodium concentration. Hyperpolarization of the membrane could not only be produced after readmission of potassium but also after addition of thallium, the latter being more potent. Raising the external chloride concentration resulted in a decrease of the K-response and membrane resistance. The current, generating the K-response was shown to be hardly influenced by conditional polarization of the membrane. It is concluded from these results that the K-response is mainly due to the operation of an electrogenic sodium pump.

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
D009130	Muscle, Smooth	Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)	Muscle, Involuntary,Smooth Muscle,Involuntary Muscle,Involuntary Muscles,Muscles, Involuntary,Muscles, Smooth,Smooth Muscles
D010042	Ouabain	A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.	Acocantherin,G-Strophanthin,Acolongifloroside K,G Strophanthin
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.
D002463	Cell Membrane Permeability	A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.	Permeability, Cell Membrane
D002712	Chlorides	Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.	Chloride,Chloride Ion Level,Ion Level, Chloride,Level, Chloride Ion
D003486	Cyanides	Inorganic salts of HYDROGEN CYANIDE containing the -CN radical. The concept also includes isocyanides. It is distinguished from NITRILES, which denotes organic compounds containing the -CN radical.	Cyanide,Isocyanide,Isocyanides
D004140	Dinitrophenols	Organic compounds that contain two nitro groups attached to a phenol.
D005260	Female		Females