Biomaterial Database

Different effects of two gold compounds on muscle contraction, membrane potential and ryanodine receptor. 1999

T Oba, and T Ishikawa, and M Yamaguchi

Department of Physiology, Nagoya City University, Medical School, Nagoya, Japan. tooba@med.nagoya-cu.ac.jp

Effects of gold sodium thiomalate and NaAuCl4 on skeletal muscle function were studied using intact single fibres of frog skeletal muscle and fragmented sarcoplasmic reticulum prepared from frog and rabbit skeletal muscles. Gold sodium thiomalate at a concentration of 500 microM decreased tension amplitude by 27% and resting membrane potential by 5.3% after 30 and 22 min, respectively. The duration of tetanus tension was markedly shortened by 500 microM gold sodium thiomalate. When 10 microM NaAuCl4 was applied to gold sodium thiomalate-pretreated fibres, the fibres lost the ability to contract upon electrical stimulation, similar to the effects of 10 microM NaAuCl4 alone. In the presence of thiomalic acid, on the other hand, NaAuCl4 did not completely block tetanus tension even at 50 microM. Thiomalic acid also inhibited NaAuCl4-induced membrane depolarization. These findings suggest that thiomalate masks the effects of gold ion on muscle function. When sarcoplasmic reticulum vesicles were incorporated into lipid bilayers, exposure of the cis side of the Ca2+-release channel to 100 microM gold sodium thiomalate rapidly increased the open probability of the channel 3.3-fold, from 0.032 in controls to 0.105, with an increase in number of open events and a decrease in mean closed time. The ability of NaAuCl4 to activate the Ca2+-release channel was much stronger than that of gold sodium thiomalate. Only 1 microM NaAuCl4 was enough to activate the channel and this gold was effective from either side of the channel. These results suggest that gold sodium thiomalate could be used as an antirheumatic drug without considering severe side-effects on skeletal muscle. Coexistent thiomalate probably contributes to protection of muscle function from side-effects of gold ion.

UI	MeSH Term	Description	Entries
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
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D011898	Ranidae	The family of true frogs of the order Anura. The family occurs worldwide except in Antarctica.	Frogs, True,Rana,Frog, True,True Frog,True Frogs
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
D002712	Chlorides	Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.	Chloride,Chloride Ion Level,Ion Level, Chloride,Level, Chloride Ion
D006052	Gold Sodium Thiomalate	A variable mixture of the mono- and disodium salts of gold thiomalic acid used mainly for its anti-inflammatory action in the treatment of rheumatoid arthritis. It is most effective in active progressive rheumatoid arthritis and of little or no value in the presence of extensive deformities or in the treatment of other forms of arthritis.	Aurothiomalate,Gold Thiomalate,Sodium Gold Thiomalate,Aurolate,Gold Disodium Thiomalate, Monohydrate,Gold Thiomalic Acid,Mercaptobutanedioic Acid Monogold(1+) Sodium Salt,Miocrin,Miocrisin,Monogold (1+) Disodium Thiomalate,Myochrysine,Myocrisin,Myocrysine,Sodium Aurothiomalate,Sodium Thiomalatoaurate,Tauredon,Aurothiomalate, Sodium,Gold Thiomalate, Sodium,Sodium Thiomalate, Gold,Thiomalate, Gold,Thiomalatoaurate, Sodium
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
D012519	Sarcoplasmic Reticulum	A network of tubules and sacs in the cytoplasm of SKELETAL MUSCLE FIBERS that assist with muscle contraction and relaxation by releasing and storing calcium ions.	Reticulum, Sarcoplasmic,Reticulums, Sarcoplasmic,Sarcoplasmic Reticulums