Biomaterial Database

Effects of diltiazem on electrical and mechanical activities of isolated guinea pig taenia coli. 1977

T Magaribuchi, and H Nakajima, and A Kiyomoto

Effects of diltiazem on electrical and mechanical activities of isolated guinea pig taenia coli were studied by means of the double sucrose-gap method. In the spontaneously active preparations, diltiazem (2.2 X 10(-6) M) suppressed both electrical activity and isometric contraction, while electrical and mechanical activities evoked by the depolarizing current pulse were not affected at the concentration of 2.2 X 10(-6) M. In the presence of 2.2 X 10(-5) M diltiazem, the evoked contractile force and the number of repetitive firings during depolarization were reduced, whereas the single spike was almost unchanged or somewhat inhibited. At 2.2 X 10(-4) M diltiazem, both electrical and mechanical activities were almost abolished. The contractile force and single spike suppressed by diltiazem were partly reversed by the addition of 5 mM CaCl2. There was little significant change in membrane potential and membrane resistance. Similar but somewhat weaker effects were observed when NaCl was replaced with sucrose. In some preparations, 2.2 X 10(-4) M diltiazem reduced the contractile force without significant influence on the electrical activity in Na+-free Locke solution. CoCl2 (3 mM) inhibited the evoked activities in both normal and Na+-free solutions. Possible mechanisms for the relaxing effects of diltiazem on isolated guinea pig taenia coli were discussed.

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
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
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
D003106	Colon	The segment of LARGE INTESTINE between the CECUM and the RECTUM. It includes the ASCENDING COLON; the TRANSVERSE COLON; the DESCENDING COLON; and the SIGMOID COLON.	Appendix Epiploica,Taenia Coli,Omental Appendices,Omental Appendix,Appendices, Omental,Appendix, Omental
D004110	Diltiazem	A benzothiazepine derivative with vasodilating action due to its antagonism of the actions of CALCIUM ion on membrane functions.	Aldizem,CRD-401,Cardil,Cardizem,Dilacor,Dilacor XR,Dilren,Diltiazem Hydrochloride,Diltiazem Malate,Dilzem,Tiazac,CRD 401,CRD401
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
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
D001552	Benzazepines	Compounds with BENZENE fused to AZEPINES.
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23