BIOMAT Database Logo BIOMAT Database Logo

Effects of 6-mercaptopurine treatment on the membrane potentials of rat skeletal muscle fibers. 1985

P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs

6-Mercaptopurine (6-MP), injected daily (2 mg/kg s.c.) into Sprague-Dawley rats during the first 3 weeks of life, causes atrophy in muscles of the hindquarters beginning at 4 months of age. The extensor digitorium longus (EDL) muscles from 24 rats injected with 6-MP and 23 saline-injected controls, 6-18 months of age, were studied. Electron microscopy showed a number of abnormalities in the EDL muscle of 6-MP-treated rats, such as myocytes with atypical ultrastructure (including disorganized myofibrils) adjacent to structurally normal cells. Membrane potentials (Em) were measured in the isolated EDL and in the caudofemoralis (CF) muscle in situ. The mean Em of fibers in the EDL of 6-MP-treated rats (-61.1 +/- 0.7 (SE) mV) was lower than that of the control rats (-69.7 +/- 0.6 mV). The same was true for the fibers of the CF muscle (-64.9 +/- 1.5 mV for 6-MP-treated fibers vs. -71.6 +/- 1.3 mV for controls). The contribution of the electrogenic pump potential to Em (+/- ouabain) was similar in 6-MP-treated and control rats, and therefore could not account for the depolarization observed in 6-MP-treated rats. This depolarization was not due to a decreased intracellular K+ concentration. The Na+:K+ permeability ratio (PNa/PK) was higher in the 6-MP-treated rats and could account for the decrease in Em.(ABSTRACT TRUNCATED AT 250 WORDS)

UI MeSH Term Description Entries
D007700 Kinetics The rate dynamics in chemical or physical systems.
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
D008839 Microelectrodes Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed) Electrodes, Miniaturized,Electrode, Miniaturized,Microelectrode,Miniaturized Electrode,Miniaturized Electrodes
D008854 Microscopy, Electron Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen. Electron Microscopy
D009132 Muscles Contractile tissue that produces movement in animals. Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
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
D011919 Rats, Inbred Strains Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding. August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
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

Related Publications

P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Dual effects of taurine on membrane ionic conductances of rat skeletal muscle fibers.
January 1994, Advances in experimental medicine and biology,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Effects of membrane potential on the capacitance of skeletal muscle fibers.
February 1976, The Journal of general physiology,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Investigating the myopathic effects of 6-mercaptopurine on developing skeletal muscle cells in vitro.
January 1984, Drug and chemical toxicology,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Effects of inactivity on membrane potentials in rat muscle.
July 1978, Brain research,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Effects of denervation and colchicine treatment on the chloride conductance of rat skeletal muscle fibers.
May 1976, Journal of neurobiology,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
[Membrane potential and action potential of rat skeletal muscle fibers].
January 1961, Comptes rendus des seances de la Societe de biologie et de ses filiales,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Effects of uridine triphosphate on skinned skeletal muscle fibers of the rat.
October 1995, Canadian journal of physiology and pharmacology,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Effects of aging on the mechanical threshold of rat skeletal muscle fibers.
March 1992, Pflugers Archiv : European journal of physiology,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Effects of vinblastine on the component conductances of rat skeletal muscle fibers.
March 1977, Pharmacological research communications,
P Clouva-Molyvdas, and N Sperelakis, and M S Forbes, and F R Alleva, and T Balazs
Cardiac glycoside effects on rat skeletal muscle potentials and electrolytes.
January 1970, Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.),
Copied contents to your clipboard!