Adrenergics: Catecholamines Flashcards
Causes peripheral excitatory action on certain types of smooth muscle (blood vessels, radial
muscle) and on glands (salivary and sweat)
Catecholamines
Drug with peripheral inhibitor action on certain types of smooth muscle (wall of gut, bronchial
tree, blood vessels supplying skeletal muscle)
Catecholamines
Causes cardiac excitatory action that increases heart rate and force of contraction
Catecholamines
Catecholamine has metabolic actions: ______ glycogenolysis (liver and muscle) and liberation of ________
Increase
FFAs
Catecholamine’s action: endocrine actions: modulate the secretion of ______ and ______
insulin DECREASE
renin INCREASE
Catecholamine actions in the CNS: respiratory ______, _______ in wakefulness and
psychomotor activity, _______ in appetite
stimulation
increase
reduction
Catecholamines have prejunctional actions that either inhibit or facilitate the release of neurotransmitters, the _____ action being most important
inhibitor
Catecholamines and adrenergic agonists are
sympathomimetics
drugs mimic the effects of transmitter substances of the sympathetic nervous system
Sympathomimetic
How do sympathomimetic drugs work?
These drugs act at the postganglionic sympathetic terminal,[1] either directly activating postsynaptic receptors, blocking breakdown and reuptake, or stimulating production and release of catecholamines.
Adrenergic antagonists are an example of
(sympatholytics)
Adrenergic antagonists: most are _______ antagonists (exception is phenoxybenzamine)
competitive
How is it possible for adrenergic anatagonists to interfere selectively with responses that result from sympathetic stimulation
compounds have been developed with different affinities for the various receptors
Adrenergic receptor subtype:
α1 located in the Eye does
Contraction of the radial muscle of the iris (mydriasis)
Adrenergic receptor subtype:
α1 located in the arteries and veins does
constriction
Adrenergic receptor subtype:
α1 located in the GU smooth muscle for male does
constriction
Adrenergic receptor subtype:
α2 located in Pre-synaptic nerve
causes Inhibition of transmitter release terminals
Adrenergic receptor subtype:
α2 located in CNS causes
Inhibition of sympathetic outflow
Adrenergic receptor subtype:
β1 located in Heart causes
Increased rate and force of contraction &
Increased A-V conduction velocity
Adrenergic receptor subtype:
β1 located in Kidney causes
Renin release
Adrenergic receptor subtype:
β2 located in Arteries (skeletal muscle)
Dialation
Adrenergic receptor subtype:
β2 located in Bronchi
Dialation
Adrenergic receptor subtype:
β2 located in skeletal muscle
Glycogenolysis
Adrenergic receptor subtype:
β2 located in liver
Glycogenolysis, gluconeogenesis
Adrenergic receptor subtype: Dopamine1
located in the Kidney causes
Dilation of kidney vasculature
Adrenergic Agonists:
Substitution of OH groups at the __ and __ position of aromatic ring is necessary for maximal α and β activity
3 and 4
Adrenergic Agonists:
Presence of 2 carbon atoms between ______ and ______the affords the greatest sympathomimetic activity.
aromatic ring and amino group
Adrenergic Agonists:
Substitution of alkyl groups on the amino group tend to ↑ ______ (i.e., isoproterenol).
β activity
Adrenergic Agonists:
phenylephrine is an
α1 agonist
Adrenergic Agonists:
What increases the oral effectiveness and duration of action of many compounds especially those with an α-CH3 group (i.e. amphetamine)
Absence of one or both OH groups (especially the 3-OH)
Adrenergic Agonists:
What makes the compound more resistant to MAO (i.e., amphetamine).
Substitution on the α carbon