Adrenergic Pharmacology

Adrenergic Receptors

Receptor	Binding Affinity	Effects	Mechanism	Agonists	Antagonists
Alpha-1	Norepi > Epi >> Iso	Smooth muscle contraction	Gq, PLC -> IP3/DAG	Norepi Phenylephrine Midodrine	Phenoxybenzamine Phentolamine Prazosin Tamsulosin Trazodone
Alpha-2	Epi = Norepi >> Iso	Mixed effects	Gi, presynaptic, cAMP down	Dexmedetomidine Clonidine	Phenoxybenzamine Phentolamine Trazodone
Beta-1	Iso > Norepi > Epi	Example	Gs, cAMP up	Dobutamine Isoprenaline Norepi	Cardiac Selective: Metoprolol Atenolol Esmolol
Beta-2	Iso > Epi > Norepi	Example	Gs, cAMP up	Albuterol Formoterol Isoprenaline Salmeterol Terbutaline Ritodrine	Non-Selective: Propranolol Nadolol Pindolol Timolol
Beta-3	Iso > Epi = Norepi	Example	Gs, cAMP up	Mirabegron	Example