Pharmacology of Adrenergic agonists and antagonists Flashcards
T/F: The adrenergic Nervous system relates to the fight or flight system of the autonomic nervous system
True
What type of receptors are the alpha and beta receptors of the adrenergic nervous system
G-coupled protein receptors
In a synapse where are the alpha 1 receptors usually located
Post synaptic membrane of effector organs
What does alpha-1 receptor activation do
contraction throughout the body (mydriasis, vasoconstriction, goosebumps)
What does beta-2 receptor activation do
relaxtion throughout the body ( vasodilation, bronchodilation)
What does beta-1 receptor activation do
increase heart rate, increased force of contraction, increased conduction velocity, renin release
What does alpha-2 receptor activation do
Inhibit norepinephrine release
What are two consequnces of using drug agonists
Desentization and Denervation
What is denervation supersensitivity
When loss of nerve occurs the effector muscle grows a much more sensitive to the neurotransmitter
What is the main neurotransmitter of the sympathetic nervous system
Norepinephrine
What are the classification for adrenergic agonists based on their structure
catecholamine and non-catecholamines
What are the classifications for adrenergic agonists based on their action
direct-acting, indirect-acting, mixed-acting
What enzymes metabolize circulating catecholamines as well as ones in the brain
COMT and MAO
T/f: Catecholamines can be given orally
False: Catecholamines are dosed IV, IM, topically, and aerosol
What property of non-catecholamines protects them from MAO metabolism
substitution on the alpha carbon
What are possible MOAs of indirect adrenergic agonists
increase availability of norepinephrine or epinephrine in the snyapse through facilitating relase of norepinephrine from sympathetic nerve endings, impair reuptake of released catecholamines, block metabolizing enzymes
What are the two drugs that work indirect by releasing norepinephrine and activate adrenergic receptors as well
Ephedrine and pseudoephedrine
What are the therapeutic uses of adrenergic agonists
Decongestion and maintain blood pressure (alpha 1)/ manage acute asthma attacks, asthma prophylaxis (beta-2 agonists)/ anaphylactic shock (epinephrine)
What are the MOA of alpha-2 agonists
inhibit the release of NE decreasing vascular tone and cardiac output
What is a common Alpha-2 agonist
clonidine
What is the result that occurs from using a L-tyrosine hydroxylase inhibitor
reduces the biosynthesis of dopamine,norepinephrine and epinephrine leading to a lower blood pressure
T/F: NE antagonists acting as a false transmitter act just like NE but do no bind correctly and take up space that could be used by NE
True
What are the results of Alpha-1 antagonsits
lower peripheral vascular resistance and lower blood pressure
What is epinephrine reversal
Epinephrine is used with an alpha-1 antagonists that causes an overall large drop in blood pressure
