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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following is not true about the mechanism of action of digitalis?
assistant
The correct answer is  Ans. is 'a' i.e., It binds to the intracellular face of Na+ K+ ATPase enzyme Digitalis mechanism of action* Digitalis increases the force of contraction by a direct action independent of the innervation.* It binds to the extracellular face of the Na+ K+ ATPase and inhibits the enzyme causing rise in the intracellular levels of Na+.* The raised Na+ in turn inhibits the Na+ Ca2+ exchanger and causes rise in intracellular Ca2+.* This raised intracellular Ca2+ is responsible for the positive ionotropic effect.* Thus, digitalis increases the cardiac contractability and force of contraction.