Receptors Flashcards
Adrenergic Receptors
respond to catecholamines such as norepinephrine and epinephrine
Where is epinephrine and norepinephrine from?
Hormones from adrenal medulla
Two kinds of adrenergic receptor
alpha and beta
what does alpha receptors respond to
respond to BOTH epinephrine and norepinephrine
where is alpha-1 receptor found?
- iris radial muscle => pupil dilation
- peripheral arterioles smooth muscles
=> vasoconstriction => increased BP - sweat glands => increased sweat
- heart muscles => increased HR
what kind of effect is alpha-1 receptor
stimulatory effect
where is alpha-2 receptor found?
- smooth muscle of GI tract => decreased peristalsis
- GI glands => decreased GI secretion
beta receptors
respond ONLY to epinephrine
where is beta-1 receptor found
- heart muscle => increased strength of contraction
- kidney cells => increased renin secretion
where is beta-2 receptor found?
smooth muscles of:
- blood vessels => vasodilation => increased blood flow
- bronchi => bronchodilation => improved ventilation
agonist
drugs that act like catecholamines when binding with receptor
antagonist or blockers
drugs that bind to receptor and block action of catecholamines
what kind of effect is alpha-2 receptors?
inhibitory effect => decreased activity
