Last updated 04/10/00 12:26 PM
3. Your patient has been treated for many years with propranolol to control his hypertension. Explain why abrupt withdrawal of the ß-blocker would be deleterious in terms of the cardiovascular reflexes and cellular mechanism(s) that underlies these effects.
Due to the many years of continued use of propranolol, the ß receptors have up-regulated. Therefore with an abrupt withdrawal you are going to have an increased number of free ß receptors. That may cause a rebound hypertension. Patient should be tapered off ß blockers therapy in order to avoid precipitation of arrhythmias.
Cellular mechanisms due to free ß1 receptors include an in SNS NE, HR, contractility, possible chest pain do to myocardial demand.
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