Cardiac glycosides increase the force of contraction of cardiac muscle cells. As the intracellular Ca concentration increases, the force of contraction increases. These drugs work by slowing down the function of the Na /K pump. Intracellular Ca concentration is regulated by secondary active transport through a Na / Ca antiporter. This means that the diffusion of Na down its concentration gradient into the cell provides the energy to transport Ca out of the cell (against its gradient). How would these drugs effect the active transport of K into the cell
