General Pharmacology-Sympathetic/Adrenergic receptors Flashcards
Alpha-1 Receptor functions
Increase vascular smooth muscle contraction
Increase Pupillary dilator muscle contraction (Mydriasis)
Increase intestinal and bladder sphincter muscle contraction
Examples of Alpha-1 Receptor agonists
Epinephrine (B1>A1) , Norepinephrine, Phenylephrin, Midodrine
Alpha-1 Receptor action
Class q (G-protein) Increases IP3/Calcium in smooth muscles
Alpha-2 Receptor action
Class i (G-protein) Decreases cAMP
Alpha-2 Receptor function
Reduces sympathetic (adrenergic) outflow Reduces insulin release Reduces Liploysis Increases Platelet aggregation Reduces aqueous humor production Reduces Intestinal motility In brainstem results Reduced sympathetic outflow from CNS --> Low PVR, low HR, low BP
Alpha-2 Receptor agonists examples
Clonidine
Beta-1 Receptor action
Class s (gprotein) INCREASES cAMP
Beta-1 Receptor function
ONE HEART Increases heart rate Increase contractility Increases renin release Increases Lipolysis
Beta-1 Receptor agonist examples
Dopamine, Dobutamine, Isopreterenol, Epinephrine (apha>beta at high doses)
Beta-2 Receptor action
Class s (gprotein) Increases cAMP in smooth muscles, peripheral vascular., bronchi, and uterus
Beta-2 Receptor function
Vasodilation (low> BP diastolic) Bronchodilation TWO LUNGS Increases Lipolysis Increases Insulin release Increases glycogenolysis Reduces uterine tone (tocolysis) Increases Aqueous humor production Increases cellular K uptake
Beta-2 Receptor agonist example
Isoprterenol, Terbutaline, Albuterol & Salmetrol
Beta- 3 Receptor function
Increases lipolysis
Increases thermongnesis in skeletal muscle
Increases bladder relaxation
Alpha-1 antagonists
Doxazocin, Terazocin (increase HR, reduce SVR), Phenoxybenzamin (Alpha & beta effect)
