Cellular mechanism of action of cardiac glycosides
It has long been known that cardiac glycosides can inhibit the membrane sodium-potassium (Na+-K+) pump, raising intracellular Na+. However, at clinical concentrations of cardiac glycosides, a change in intracellular Na+ that correlates with a change in cardiac contraction has been very difficult to demonstrate. The recent use of Na+-sensitive microelectrodes in the experimental laboratory has made intracellular Na+ measurements possible. A doubling of contraction strength in vitro is associated with a change of only approximately 1 mM intracellular Na+. Another membrane transport system, the Na+-Ca2+ exchange system, exchanges extracellular Na+ for intracellular Ca2+. If this system is responsible for regulating intracellular Ca2+, then it would be very sensitive to the transmembrane Na+ concentration gradient. This influence of intracellular Na+ on Na+-Ca2+ exchange is though to be the cellular basis of the positive inotropic action of digitalis. However, a number of issues remain unresolved, such as the extent of Na+-K+ pump inhibition by the level of cardiac glycoside achieved clinically.
Stimulation and inhibition of the sodium pump by cardioactive steroids in relation to their binding sites and their inotropic effect on guinea-pig isolated atria
Inotropic effects and changes in sodium and calcium contents associated with inhibition of monovalent cation active transport by ouabain in cultured myocardial cells
The effects of external cations and ouabain on the intracellular sodium activity of sheep heart Purkinje fibres
Effect of solubilization on adenosine 5'-triphosphate induced calcium release from purified sarcoplasmic reticulum calcium adenosinetriphosphatase
Transmembrane Na+ and Ca2+ electrochemical gradients in cardiac muscle and their relationship to force development
Relation between intracellular sodium and twitch tension in sheep cardiac Purkinje strands exposed to cardiac glycosides
Excitation-contraction coupling in cardiac Purkinje fibers. Effects of cardiotonic steroids on the intracellular [Ca2+] transient, membrane potential, and contraction
Excitation-contraction coupling in cardiac Purkinje fibers. Effects of caffeine on the intracellular [Ca2+] transient, membrane currents, and contraction
The effects of membrane potential, extracellular potassium, and tetrodotoxin on the intracellular sodium ion activity of sheep cardiac muscle
Measurement of cytosolic free calcium concentration in isolated rat ventricular myocytes with quin 2
Effect of strophanthidin on intracellular Na ion activity and twitch tension of constantly driven canine cardiac Purkinje fibers
The dependence of sodium pumping and tension on intracellular sodium activity in voltage-clamped sheep Purkinje fibres
Differing sensitivities of Purkinje fibers and myocardium to inhibition of monovalent cation transport by digitalis
Reassessment of digoxin and other low-dose positive inotropes in the treatment of chronic heart failure
Modification of Ca(2+)-handling in cardiomyocytes by redox sensitive mechanisms in response to ouabain
Effects of cardiac glycosides on atrial contractile dysfunction after short-term atrial fibrillation
Acute hemodynamic effects of digoxin alone or in combination with other vasoactive agents in patients with congestive heart failure
Search for intermediates of Na+,K+-ATPase-mediated [Na+]i/[K+]i-independent death signaling triggered by cardiotonic steroids
Intravenously administered digoxin in patients with acute atrial fibrillation: a population pharmacokinetic/pharmacodynamic analysis based on the Digitalis in Acute Atrial Fibrillation trial
Drug discovery with an RBM20 dependent titin splice reporter identifies cardenolides as lead structures to improve cardiac filling
Inotropic response to hypothermia and the temperature-dependence of ryanodine action in isolated rabbit and rat ventricular muscle: implications for excitation-contraction coupling
An antagonist of cADP-ribose inhibits arrhythmogenic oscillations of intracellular Ca2+ in heart cells.
Development and Validation of a UHPLC-ESI-MS/MS Method for Quantification of Oleandrin and Other Cardiac Glycosides and Evaluation of Their Levels in Herbs and Spices from the Belgian Market.
Triple-negative breast cancer cell line sensitivity to englerin A identifies a new, targetable subtype.
Sarcolemmal cation channels and exchangers modify the increase in intracellular calcium in cardiomyocytes on inhibiting Na+-K+-ATPase
Involvement of sarcoplasmic reticulum in changing intracellular calcium due to Na+/K+-ATPase inhibition in cardiomyocytes
Effect of Digoxin on Ventricular Remodeling and Responsiveness of beta-Adrenoceptors in Chronic Volume Overload
Digoxin's Minimal Inotropic Effect Is Not Limited by Sodium-Calcium Exchange in the Intact Immature Rabbit Heart
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Cardiac glycosides are a diverse family of naturally derived compounds that bind to and inhibit na+/k+-atpase. Discover the latest research on cardiac glycosides heres.