Digitalis glycosides Foxglove

Cardiovascular Digitalis-like glycosides - Foxglove (Digitalis Contain glycosides that are... 

The positive benefits of extracts of two species of Digitalis purpurea (foxglove and lanata) were recognized long before the active constituents were isolated and structurally characterized. The cardiac glycosides, which include digoxin, digitoxin, and deslanoside, exert a powerful and selective positive inotropic action on the cardiac muscle (see Chapter 35). 

Chronic toxicity develops following the use of herbal products or teas that contain foxglove. The development of toxicity is unpredictable since the digitalis glycoside content of these products is not standardized. This is now extremely rare. 

The outcome of this is to couple ATP hydrolysis with the vectorial transport of Na+ and K+ across the plasma membrane. The inhibition of the (Na+-K+)-ATPase by cardiac glycosides such as digitalis (an extract of foxglove leaves), which blocks the dephosphorylation of the E2-P form of the enzyme, is the basis for a number of steroid drags which are commonly prescribed for the treatment of congestive heart failure. 

Glycosides isolated from leaves of various types of foxglove Digitalis lanta. Digitalis purpurea, and strophanthus Strophantus kombe, and also a number of other plants (hhes, periploca, oleander, hellebore, erysimum, jute, Irish ballon), which exhibit a direct effect on the myocardium and which strengthen its contractions. 

Cardiac steroids, or cardenoUdes, are steroid glycosides. Their effect has been known since the time of the ancient Egyptians. In more recent times, the foxglove (Digitalis purpurea) and its effect were described in 1785 by William Withering, who knew of its use in folk medicine. 

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