Sympathomimetics part 1 Flashcards
Nurse anesthesia is the practice of __ nervous system nursing
autonomic
Name three Naturally occurring catecholamines
epinephrine
NE
dopamine
Name two Synthetic catecholamines
isoproterenol
dobutamine
Name some Synthetic non-catecholamines
ephedrine amphetamines phenylephrine methoxamine mephentermine
__ isomers have all the adrenergic power – just remember Levophed
Levorotary
Six steps for adrenergic transmission, uses NE instead of ACh
SYNTHESIS STORAGE RELEASE via Ca++ mediated exocytosis BINDING DEGRADATION RECYCLING
__ and __ are the receptor ligands for α1, α2, or β adrenergic receptors. __ and __ binding to receptors alter the chemical conformation – three dimensional shape of the receptor.
Epi & NE
Epi & NE
Sympathomimetics work at __-ganglionic in the SNS at effector organ receptor sites. (Remember, pre-ganglionic adrenergic neurons have Ach for their neurotransmitter)
POST
Alpha and beta receptors MUST HAVE __ or __ as the neurotransmitter, NOT dopamine
Epi & NE
What do alpha 1 agonists do?
VASOCONSTRICTION, mydriasis, relaxation of GI, contraction of GI sphincters, contraction of bladder sphincters = HIGH BP, NO PEE/POOP, PHENYLEPHRINE, levophed, methoxamine
What do alpha 2 agonists do?
inhibition of NE (post-synaptic), platelet aggregation, hyperpolarization of cells in the CNS, sedation = DEXMEDETOMIDINE, CLONIDINE
two alpha 1 antagonists you should probably know
phentolamine and phenoxybenzamine - for vasopressor extravasation and in preparation for pheochromocytoma
one alpha 2 antagonist you should probably know
yohimbe
What do beta 1 agonists do?
positive inotropes
Beta 1 agonists
isoproterenol, dobutamine, epi, NE
beta 1 antagonists
metoprolol, atenolol
What do beta 2 agonists do?
smooth muscle relaxation
Beta 2 agonists
albuterol, terbutaline, isoproterenol
beta 2 antagonists
propranolol
beta 3 antagonists
double cheeseburgers
How are catecholamines metabolized?
monoamine oxidase (MAO), and catechol-O-methyltransferase (COMT)
Despite metabolism, how are the actions of catecholamines terminated?
reuptake into the postganglionic sympathetic nerve endings
Synthetic non-catecolamines not affected by COMT or MAO?
not affected by COMT, depend on MAO
Where do direct acting sympathomimetics work?
Direct acting agonists act at post-synaptic receptors.
Where do indirect acting sympathomimetics work?
Indirect acting agonists release neurotransmitters from pre-synaptic nerve terminals to produce a sympathomimetic effect.
How do Synthetic indirect acting non-catecholamines work?
Synthetic non-catecholamines activate adrenergic receptors by evoking release of NE from post ganglionic sympathetic nerve endings
-ephedrine, cocaine, amphetamine
Does your patient need an endogenous storage of NE to have an effect from an indirect acting?
Yes. But not a direct acting such as Epi, NE, or dobutamine, they act directly all by themselves.
Two structural classes of alpha1 agonists
phenethylamines - related in structure to epi
imidazolines -related in structure to Afrin
how to make epi
Tyrosine –> DOPA –> dopamine –> NE –> epi
