How does propranolol (Inderal), a beta blocker medication, control hypertension?

Choice A reason: This is the correct mechanism of action of propranolol. Propranolol is a beta blocker medication, which means that it blocks the beta receptors in the heart and blood vessels. This reduces the sympathetic stimulation in cardiac muscle, which lowers the heart rate, contractility, and oxygen demand. This also reduces the renin release from the kidneys, which lowers the blood pressure. Choice B reason: This is not the mechanism of action of propranolol. Propranolol does not increase the diuretic response in the renal tubules. This is the effect of diuretic medications, such as furosemide or hydrochlorothiazide, which increase the urine output and decrease the blood volume and pressure. Choice C reason: This is not the mechanism of action of propranolol. Propranolol does not inhibit the conversion of angiotensin I to angiotensin II. This is the effect of angiotensin-converting enzyme (ACE) inhibitors, such as lisinopril or enalapril, which block the formation of angiotensin II, a potent vasoconstrictor that raises the blood pressure. Choice D reason: This is not the mechanism of action of propranolol. Propranolol does not block alpha receptors throughout the body. This is the effect of alpha blockers, such as doxazosin or prazosin, which block the alpha receptors in the blood vessels and cause vasodilation, which lowers the blood pressure.