Adrenergic Flashcards
(33 cards)
Adrenergic neurons secrete what
Norinephrine
Presynaptic receptor controls the release of what?
Norepinephrine
Sns fight and flight responses
Mydrasis, increased cardiac output, bronchidilation, glycogen lysis, reduction in gi secretions/motility, relaxation of smooth muscle in urinary bladder, decreased blood flow for renal and mesenteric blood vessel construction, vasodilation to skeletal muscle, increased sweat, increase epinephrine from adrenal glands
What adrenergic receptors are passive
B 2/3
Catacholines in adrenergic
Epinephrine, dopamine, noriepinephrine, dopamine, isoproterenol, dobutamine
Noncatacholamines
Albuterol, phenylephrine, and ephedrine
Important difference between catacholamines and noncatacholamines
Catacholamines Low availability values when taken orally because they are quickly metabolized by intestinal and hepatic MAO AND COMT. They have short duration of action and half life
Non catacholamines
Due to absence of hydroxyl group noncatacholamines are less polar/more lipid soluble, and can pass the BBB and produce more central effects
Propanolol has had Significant ___________ metabolism
First pass
Methyl-tyrosine
Treatment of pheochromocytoma. It is a tumor of adrenal medulla that is associated with excessive production of catacholamines and development of severe hypertension
How to test for pheochromocytoma
24 hour urine to test for epinephrine levels
Generalized sympathomimetics means
Adrenergic agonists, non selective receptors
Generalized sympathomimetics med examples and MOA
Epi is alpha 1/2 and beta 1/2 which induces fight or flight.
Dopamine is d1, beta1 and alpha 1 agonist
What is epinephrine used for
Eye drops inducing dilation, bronchodilation for asthma patients, anaphylaxis,
What is dopamine used for
Cardiogenic shock on renal d1 receptor agonist that mediates mesenteric blood vessel vasodilation to increase renal blood flow, prevents renal failure.
How does affinity and dopamine relate to receptors
D1 highest affinity needs lowest dose to reach them, followed by b1, then alpha 1
Why does inhaled epinephrine used to treat asthma cause tachycardia
Because epinephrine is a non selective adrenergic agonist
Selective alpha adrenergic receptor sympathomimetics and MOA
Phenylephrine, tetrahydrozoline, and clonidine
Phenylephrine (used for vasoconstriction, nasal decongestant, treat priapism with prolonged responses to sildenafil (viagra) and tetrahydrozoline (what’s in visine to constrict blood vessels and make them not red ) are alpha 1 agonists
Clonidine passes bbb and acts as alpha 2 agonist which reduced release of catacholamines and sns tone. Acts as antihypertensive
Selective beta adrenergic receptor sympathomimetics examples and MOA
Isoproterenol - generalized beta 1/2 adrenergic receptor agonist
Dobutamine - selective beta 1 agonist
Albuterol and terbutaline- selective beta 2 agonist
Mirabegron- selective beta 3 agonist
Isoproterenol and dobutamine therapeutic affects
Cardiac stimulants, used in treatment of cardiac arrest and heart failure
Albuterol is a commonly used bronchodilator t/f
True
Terbutaline is used for
Used to reduce myometrial uterine contractions and prevent preterm birth.
Mirabegron
Activates beta3 on derisory muscles and serves as antispasmodic that is treatment of urinary incontinence
Indirect acting and mixed acting sympathomimetics example and MOA
Amphetamines are transported into the sympathetic axon terminal where is displaced catacholamines from internal stores. This effect results in release of NE into synapse indirect sympathomimetic
Ephedrine also displaces NE from internal stores (slow displacement) and is a weak a1/a2 agonist
