Biomaterial Database

Effect of the calcium channel agonist Bay K8644 on mechanical and electrical responses of frog skeletal muscle. 1994

M Oz, and G B Frank

The effects of Bay K8644, a Ca2+ channel agonist, on the mechanical and electrical properties of frog skeletal muscle fibers were investigated. At relatively low concentrations, such as 10(-6) and 10(-5) M, Bay K8644 significantly potentiated the maximum amplitudes of twitch responses, and this effect was not reversed in the presence of the calcium channel antagonist nitrendipine. At higher concentrations, such as 10(-4) M, Bay K8644 depressed the amplitudes of twitch responses, and nitrendipine did not change this effect. At all concentrations, Bay K8644 greatly reduced the area under the tetanic force versus time curve, and this effect was not modified by the concomitant application of Bay K8644 and nitrendipine. Intracellular recordings revealed that the depressing effect of Bay K8644 on tetanic contractions was due to the blockade of sodium action potentials. In conclusion, the present results suggest that the modulation of twitch responses by calcium channel agonist and antagonists, at the concentration range used, is not related to the expected modulation of voltage-sensitive slow calcium channels in frog skeletal muscle fibers, and tetanic contractions are depressed by the calcium channel agonist Bay K8644 through its effect on sodium channels.

UI	MeSH Term	Description	Entries
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
D009568	Nitrendipine	A calcium channel blocker with marked vasodilator action. It is an effective antihypertensive agent and differs from other calcium channel blockers in that it does not reduce glomerular filtration rate and is mildly natriuretic, rather than sodium retentive.	Balminil,Bay e 5009,Bayotensin,Baypresol,Baypress,Gericin,Jutapress,Nidrel,Niprina,Nitre AbZ,Nitre-Puren,Nitregamma,Nitren 1A Pharma,Nitren Lich,Nitren acis,Nitrend KSK,Nitrendepat,Nitrendi Biochemie,Nitrendidoc,Nitrendimerck,Nitrendipin AL,Nitrendipin Apogepha,Nitrendipin Atid,Nitrendipin Basics,Nitrendipin Heumann,Nitrendipin Jenapharm,Nitrendipin Lindo,Nitrendipin Stada,Nitrendipin beta,Nitrendipin-ratiopharm,Nitrendipino Bayvit,Nitrendipino Ratiopharm,Nitrensal,Nitrepress,Tensogradal,Trendinol,Vastensium,nitrendipin von ct,nitrendipin-corax,Nitre Puren,NitrePuren,Nitrendipin ratiopharm,Nitrendipinratiopharm,nitrendipin corax,nitrendipincorax
D011894	Rana pipiens	A highly variable species of the family Ranidae in Canada, the United States and Central America. It is the most widely used Anuran in biomedical research.	Frog, Leopard,Leopard Frog,Lithobates pipiens,Frogs, Leopard,Leopard Frogs
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
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
D001498	3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester	A dihydropyridine derivative, which, in contrast to NIFEDIPINE, functions as a calcium channel agonist. The compound facilitates Ca2+ influx through partially activated voltage-dependent Ca2+ channels, thereby causing vasoconstrictor and positive inotropic effects. It is used primarily as a research tool.	BK-8644,Bay R5417,Bay-K-8644,Bay-K-8644, (+)-Isomer,Bay-K-8644, (+-)-Isomer,Bay-K-8644, (-)-Isomer,Bay-K8644,Bay-R-5417,BK 8644,BK8644,Bay K 8644,Bay K8644,Bay R 5417,BayK8644,BayR5417,R5417, Bay
D018482	Muscle, Skeletal	A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.	Anterior Tibial Muscle,Gastrocnemius Muscle,Muscle, Voluntary,Plantaris Muscle,Skeletal Muscle,Soleus Muscle,Muscle, Anterior Tibial,Muscle, Gastrocnemius,Muscle, Plantaris,Muscle, Soleus,Muscles, Skeletal,Muscles, Voluntary,Skeletal Muscles,Tibial Muscle, Anterior,Voluntary Muscle,Voluntary Muscles
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In