How come both digitalis and dihydropyridines increase the PR interval when one increases intracellular calcium concentration while one decreases calcium concentration?
Digitalis and Dihydropyridines
- Thread starter seaotter1
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Think about the sympathetic/parasympathetic effect of dig.
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I don't think people know the exact ways that digitalis works to increase PR but it is believed that it acts centrally (parasympathetic) to increase Ach release to m2 receptor.
Also, it helps to think of digitalis working on the myocardiocyte (muscle of the heart) and verapamil/diltiazam working on the nodal tissue in the sa/av node.
the 'dipines' work more in the vessels and could cause potential reflex tacky due to vasodilation...
Also, it helps to think of digitalis working on the myocardiocyte (muscle of the heart) and verapamil/diltiazam working on the nodal tissue in the sa/av node.
the 'dipines' work more in the vessels and could cause potential reflex tacky due to vasodilation...
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