Biomaterial Database

[Pharmacokinetics and action of digitoxin and ouabain in the isolated hearts of guinea pigs and rats]. 1975

K Pfleger, and N Kolassa, and W Heinrich, and M Schneider

Isolated guinea pig and rat hearts were perfused with 3H-digitoxin and 3H-ouabain. After varying perfusion periods (3-90 min) the glycoside content in the tissue was determined. With digitoxin the tissue/medium-ratio at equilibrium was found to be 14 in guinea pigs and 8 in rats, with ouabain the corresponding values were 2 and 1. In further experiments the efflux of radioactivity from isolated perfused hearts preloaded with 3H-glycosides was measured in 3 min intervals. A compartmental analysis was carried out. The efflux could be described by the sum of two exponentials indicating the existence of two compartments. The half lives of compartment 1 (2.1-4.0 min) and those of compartment 2 (16.8-20.6 min) were similar with both glycosides and both species. The development and decline of the positive inotropic effect in guinea pig hearts exhibited a time course similar to that of the glycoside content in compartment 1: the time for reaching the half maximum effect was 3-4 min with ouabain and 5-6 min with digitoxin. It is suggested that compartment 1 represents the site of the positive inotropic action of cardiac glycosides.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009200	Myocardial Contraction	Contractile activity of the MYOCARDIUM.	Heart Contractility,Inotropism, Cardiac,Cardiac Inotropism,Cardiac Inotropisms,Contractilities, Heart,Contractility, Heart,Contraction, Myocardial,Contractions, Myocardial,Heart Contractilities,Inotropisms, Cardiac,Myocardial Contractions
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
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
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D004074	Digitoxin	A cardiac glycoside sometimes used in place of DIGOXIN. It has a longer half-life than digoxin; toxic effects, which are similar to those of digoxin, are longer lasting. (From Martindale, The Extra Pharmacopoeia, 30th ed, p665)	Coramedan,Digimed,Digimerck,Digitaline Nativelle,Digitoxin AWD,Digitoxin Bürger,Digitoxin Didier,Digitoxin-Philo,Digophton,AWD, Digitoxin,Bürger, Digitoxin,Didier, Digitoxin,Digitoxin Philo,Nativelle, Digitaline
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
D006207	Half-Life	The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity.	Halflife,Half Life,Half-Lifes,Halflifes
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