Adrenoreceptors Flashcards
α1 receptor (G protein and effect)
Gq protein –> increase IP3 and DAG
common to all alpha 1
α2 receptor (G protein and effect)
Gi protein –> decrease cAMP
common to all alpha 2
β type receptor (G protein and effect)
Gs protein –> increase cAMP
common to all beta type
Dopamine D1 and D5 receptors (G protein and effect)
Gs protein –> increase cAMP
Dopamine D2, D3, D4 receptors
Gi protein –> decrease cAMP
α1 receptor action on most vascular smooth muscle
contraction
α1 receptor action of pupillary dilator muscle
contraction (dilates pupils)
α1 receptor action on prostate
contraction
α1 receptor action on heart
increases force of contraction
α2 receptor action on platelets
aggregation
α2 receptor action on adrenergic and cholinergic nerve terminals
inhibits neurotransmitter release
α2 receptor action on some vascular smooth muscle
contraction
α2 receptor action on fat cells
inhibits lipolysis
β1 receptor action on heart
increases force and rate of contraction
β1 receptor action on juxtaglomerular cells
increases renin release
β2 receptor action on respiratory, uterine and vascular smooth muscle
promotes smooth muscle relaxation
β2 receptor action on skeletal muscle
promotes potassium uptake
β2 receptor action on human liver
activates glycogenolysis and gluconeogenesis
β3 receptor action on bladder
relaxes detrusor muscle
β3 receptor action on fat cells
activates lipolysis
D1 action on smooth muscle
dilates renal blood vessels
D2 action on nerve endings
modulates transmitter release
