This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Digitalis, Subject name: Pharmacology
All are true statement about digitalis action EXCEPT: 
Select and explain. 
A. Increases cardiac contraction, B. Pumps sodium out of cell, C. Increases intracellular calcium, D. Causes bradycardia
B: Pumps sodium out of cell
Answer: B: Pumps sodium out of cell 
Explanation: Ans. (b) Pumps sodium out of cell* Digitalis is one of the cardiac glycosides which increases myocardial contractility and output in a hypodynamic heart without a proportionate increase in oxygen consumption.* Compounds in cardiac glycosides group include: digoxin, digitoxin, strophanthin, ouabain etc.* MOA of Digitalis: binds to Na+K+ATPase of myocardial fibres and inhibits this enzyme. This leads to progressive accumulation of Na+ intracellularly which indirectly results in intracellular Calcium accumulation.* ACTION:# Digitalis increases the force of contraction and decreases the heart rate# It also decreases the AV conduction, hence contraindication in WPW syndrome.# Causes diuresis in CHF patients# Causes decrease in peripheral resistance in CHF patients (because of withdrawal of reflex sympathetic overactivity)