Antihypertensive effects of propranolol are due to

• (1) decreased myocardial contractility and rate and

•  (2) to consequences of decreased renin secretion. Both effects occur as a consequence of beta-adrenoceptor blockade

•  Decreased renin levels lead to decreases in circulating angiotensin II and effects on aldosterone levels.

• Propranolol is an example of a non-selective beta blocker, antagonizing both beta-1 (cardiac) and beta-2 (extra-cardiac) sites.

Beta receptor blockade causes decreased myocardial contractility, increases in serum triglycerides and decreases in HDL cholesterol levels and increases in bronchial smooth muscle tone.