Search results for "Digitoxin"
showing 5 items of 15 documents
Über «therapeutische» und «toxische» Digitoxigeninwirkungen auf elektrophysiologische Messgrössen des Meerschweinchenvorhofs
1963
‘Therapeutic’ concentrations of digitoxigenin (10−7−3× 10−7 g/ml), producing positive inotropic effects, did not alter resting and action potentials of electrically driven guinea-pig auricles. However, ‘toxic’ concentrations of digitoxigenin (5 × 10−7−10−8 g/ml), producing arrhythmias and contracture of the myocardium, had a marked influence upon resting and action potentials and conduction velocity.
�ber die Wirkung von Strophanthidin-3-bromacetat am Papillarmuskel des Meerschweinchens
1971
In experiments on isolated, electrically stimulated papillary muscles or auricles of guinea pig hearts some characteristics of the inotropic action of strophanthidin-3-bromaocetate (SBA), a derivative of k-strophanthidin which is supposed to be an irreversible inhibitor of the (Na+-K+)-activated ATPase, were studied and compared with the behaviour of k-strophanthidin and digitoxin.
Die Reversibilität der Wirkung von Digitoxin, Strophanthidin und Strophanthidin-3-bromazetat am Papillarmuskel und einer mikrosomalen Na+-K+-aktivier…
1969
The reversibility of the inhibitory action of strophanthidin, strophanthidin-3-bromoacetate, and digitoxin on the Na+-K+-ATPase activity (microsomal fraction, guinea-pig brain) was compared with the rate of decline of their positive inotropic effects (papillary muscle, guinea-pig heart) after exposure to drug-free solution. The actions of strophanthidin and digitoxin were easily reduced on both systems. Strophanthidin-3-bromoacetate, however, was found to have an irreversible blocking effect on the transport ATPase, whereas its inotropic action could be rapidly abolished.
Über die Beeinflussung der Ca-Aufnahme in Lipidextrakte aus Mikrosomen und Mitochondrien des Herzens durch Digitoxin
1970
Lipids were isolated by chloroform-methanol extraction from mitochondrial and microsomal fractions of guinea-pig hearts. In the presence of digitoxin (10−9-10−6 g/ml) 15–30% more radioactive Ca was taken up by the lipid extracts than under control conditions, but the total amount of Ca in this phase remained unchanged. Thus, digitoxin produced an increase in the specific activity of the lipid-bound Ca which may be explained by an increased exchangeability of this Ca fraction. This effect of digitoxin might result in an improved availability of the lipid-bound Ca for Ca-dependent functions (e.g. contraction) of the heart muscle cell.
In vitro-Untersuchungen über den Einfluß von Digitoxin auf die Aufnahme von Calcium in Lipoidextrakte aus dem Herzmuskel / In-Vitro Studies of the Ef…
1969
In fruheren Versuchen an isolierten subcellularen Strukturen des Hundeherzens war eine Freisetzung von gebundenem Ca durch Herzglykoside beschrieben worden [3–5]. Da das cellular gebundene Ca vorwiegend in einer Bindung an die Lipoidkomponente der Membranstrukturen vorzuliegen scheint [1], wurde gepruft, ob Digitalis die Ca-Bindung an Lipoide zu beeinflussen vermag. Aus Meerschweinchenherzen wurden Mito-chondrien und Mikrosomen isoliert, die Lipoide extrahiert [2] und anschliesend nach der Methode von Nayler[6] die Aufnahme von Ca in diese Extrakte bei Aquilibrierung mit 45Ca-haltiger Tyrodelosung (1, 8 mM [Ca]) bestimmt. Bei Anwesenheit von Digitoxin wurde in einem Konzentrationsbereich vo…