How is mechanism of action of beta blockers?

Cardiac effects (b1) [decrease SA HR, decrease CO thus lowering BP, decreased myocardial contractility decreased cardiac work and O2 consumption, slow down AV conduction, membrane stabilizing (MSA)] Renal effect (inhibit secretion of renin (b1)) Bronchial effect (Bronchoconstriction (b2)) Metabolic effect (block glycogenesis and prevent glucose mobilization in response to hypoglycemia [B2], reduce HDL and increase LDL and TGs [b1]) Note that selective b1 blockers improve lipid profile unlike nonselective since b2 action causes vasorelaxation thus better action of endothelial lipoprotein lipase action