EFFECTS OF ADRENERGIC AGONISTS AT RECEPTORS Flashcards
When stimulated by adrenergic agonist drugs, what physiological effects do alpha 1 receptors do?
There will be an increased heart rate and contraction; vasoconstriction of blood vessels, increasing blood pressure; dilation of pupils (mydriasis); decreased secretion of salivary glands; increased relaxation of urinary bladder and urinary sphincter.
The patient took an adrenergic agonist drug mostly for alpha 1 receptor, what effects do you expect?
Increased blood pressure, dilation of pupils, increased urination, and decreased secretion from salivary glands
The patient just took an adrenergic agonist drug mostly affecting the Alpha 2 receptor, what effects do you expect?
Since adrenergic agonist drugs inhibits release of norepinephrine, vasodilation will occur, so hypotension occurs. Alpha 2 receptors act when too much stimulation by the alpha 1 receptor occurs. Alpha 2 also decreases gastrointestinal motility and tone.
Where are alpha-adrenergic receptors located?
Vascular tissue (vessels) in muscles.
Where is the alpha 2 receptor located?
Postganglionic sympathetic nerve endings.
Which neurotransmitter do adrenergic agonists mimic? From which system?
Sympathetic Nervous System’s neurotransmitter(s) norepinephrine and epinephrine
Which organs do beta 1 receptors stimulate?
Heart and kidneys
What physiological effects occur when beta 1 receptors are stimulated?
The kidneys increase release of renin which increases blood pressure. So there will be an increase in heart rate and contraction
What physiological effects occur when beta 2 receptors are stimulated?
Dilation of bronchioles; promotes gastrointestinal and uterine relaxation; increased blood sugar; and increases blood flow in skeletal muscles
What kind of patients will benefit from adrenergic agonist drugs affecting beta 2 receptors?
Commonly those who have trouble breathing; COPD patients, patients with asthma
Which adrenergic receptor can only be activated by dopamine?
Dopaminergic receptor
What is the role of dopaminergic receptor?
When stimulated, the vessels dilate and blood flow increases