Direct Adrenergic Agonist Drugs Flashcards
effect of epinephrine on cardiac function (B1 receptors)
- increases force of heart contraction (increase inotropy)
- increase HR
- increase conduction velocity at AV node
effect of epinephrine on vascular tone (B2 and A1 receptors)
- increase systolic BP
- may decrease diastolic BP and PVR
effect of epinephrine on respiratory system
- relaxes bronchial muscle (B2)
- decreases bronchial secretion and congestion within bronchial mucosa (a1)
effect of epinephrine on skeletal muscle
- muscle tremors (B2)
- increases K+ uptake by skeletal muscle (B2)
effect of epinephrine on blood glucose levels (B2)
enhances liver glycogenolysis and gluconeogenesis
effect of epinephrine on blood free fatty levels (B receptors)
increases
effect of epinephrine on renin release (B1)
increases
effect of NE on cardiac function
- cardiac stimulator, but reduces heart rate
effect of NE on bronchodilation and vasodilation
NO effect - NE lacks B2 agonist effects
effect of NE on PVR and BP
increases them
effect of NE on vasoconstriction/dilation
potent vasoconstrictor
what receptors does NE affect
- a1 = a2
- B1»_space; B2
what receptors does phenylephrine affect
a1 > a2»_space;»> B
alpha agonist
effect of phenylephrine on cardiac function
- increase BP
- severe bradycardia
effect of phenylephrine on vasoconstriction/dilation
severe vasoconstriction
what receptors does clonidine affect
a2 > a1»_space;»> B
selective a2 agonist
effect of clonidine on sympathetic outflow
decreases it
effect of clonidine on cardiac function
- reduces BP
- bradycardia
local application of clonidine causes ___
vasoconstriction
effect of clonidine on NE release
regulates it via presynaptic a2 adrenoceptors
decreases its release accordingly
what receptors does isoproterenol affect
B1 = B2»_space;» a
non-selective beta agonist
effect of isoproterenol on cardiac function
- positive inotropic and chronotropic action
- increases CO (B1)
effect of isoproterenol on vasoconstriction/dilation and arterial pressure
- vasodilator
- decreases arterial pressure (B2)
effect of isoproterenol on respiratory function
causes bronchodilation (B2)
what receptors does dobutamine affect
B1 > B2, alpha1
selective B1 agonist with some alpha1 activity
describe the alpha 1 activity of dobutamine
(-) isomer is an agonist while (+) isomer is an antagonist
effect of dobutamine on cardiac function
- potent inotropic action
- less prominent chronotropic action compared to isoproterenol
what receptors does albuterol affect
B2 > B1»_space;» alpha
selective B2 agonist
effects of albuterol on respiratory function
bronchodilation
effects of albuterol on uterus
relaxes it
what receptors does dopamine affect
D1 = D2»_space; B1»_space; a1
effect of dopamine on D1 receptor
vasodilation
effect of dopamine on presynaptic D2 receptor
suppresses NE release
effect of dopamine on cardiac function
activates B1 receptor in heart (at higher doses)
- increase force and rate of contraction
effect of dopamine on vasoconstriction/dilation
stimulates vascular a1 receptors to cause vasoconstriction (at higher doses)
