FB - Adrenergics and Antiadrenergics Flashcards
Which receptors do the autonomic nervous system parasympathetic and sympathetic innervation of the HEART act on?
Parasympathetic: M2 receptors
Sympathetic: Beta-1 receptors
Which receptors do the autonomic nervous system parasympathetic and sympathetic innervation of the LUNGS act on?
Parasympathetic: M3 receptors
Sympathetic: Beta-2 receptors
Name a drug that would have a direct sympatholytic effect on eccrine sweat glands?
Atropine or any other drug acting as an antagonist at M3 receptors
Which subtype of dopamine receptors is important on renal blood vessels?
D1
What is the major renal effect of dopamine?
Increased diuresis
Why is propranolol is not suitable for treatment of glaucoma?
Propranolol has local anaesthetic-like direct membrane effects which block the protective blink reflex.
Beta blockers selected for ophthalmic use for the treatment of glaucoma have little or no….
Low lipophilicity and hence low local anaesthetic-like direct membrane effect
When is postural hypotension in a patient prescribed an alpha-1 adrenoceptor antagonist is likely to be worst?
After the first dose
What is a common adverse effect of all alpha-2 adrenoceptor agonists?
Dry mouth
What adverse effect is commonly caused by alpha adrenoceptor antagonists that cross the blood brain barrier?
Drowsiness
Classify the prazosin according to the nature of its adrenergic/antiadrenergic activity.
Direct sympatholytic alpha-1 adrenoceptor antagonist
Classify the betaxolol according to the nature of its adrenergic/antiadrenergic activity.
Direct sympatholytic beta-1 adrenoceptor antagonist
Ephedrine is a/an
Indirect sympathomimetic increasing availability of norepinephrine through competing with norepinephrine for reuptake and vesicular reuptake while competitively inhibiting monoamine oxidase A (MAO-A). It also has direct alpha and beta-adrenoceptor agonist activity.
A direct antiadrenergic prescribed for patients with angina pectoris?
Propranolol (or other beta-blockers)
Nonselective beta-adrenoceptor antagonist used for the treatment of
glaucoma?
Timolol
Selective beta-1 adrenoceptor antagonist used for the treatment of
glaucoma?
Betaxolol
Non-selective direct alpha-adrenoceptor agonist used as a decongestant?
Oxymetazoline
An indirect sympathomimetic drug that blocks presynaptic reuptake of noradrenaline
Tricyclic antidepressant
Effect of activation of the sympathetic nervous system on airways?
Bronchodilation and increase mucociliary clearance
Precursor of norepinephrine in the postganglionic sympathetic nervous system
Dopamine
Rate limiting enzyme in epinephrine synthesis
Tyrosine hydroxylase
List the receptors activated in effector organs by the sympathetic nervous system
Alpha-1 and -2 adrenoceptors, beta-1, -2, and -3 adrenoceptors , D1, M3
Effect of activation of alpha-1 adrenoceptors on the pupil of the eye?
Dilation of the pupil (mydriasis)
Activation of alpha-1 and beta adrenoceptors in the eye BLURS…
Accommodation for near vision
What is the effect of ANTAGONISM of beta-1 adrenoceptors in the ciliary body of the eye on intraocular pressure (IOP)
Reduces intraocular pressure
Activation of alpha-1 and alpha-2 adrenoceptors generally shuts down…
GIT & visceral functions
Effect of activation of alpha-1 and alpha-2 receptors on visceral blood vessels?
Vasoconstriction
Effect of activation of alpha-2 adrenoceptors in the salivary glands?
Inhibits salivation
Effect of activation of beta-3 adrenoceptors on the bladder?
Relaxation
Activation of which adrenoceptor subtype induces bronchodilation in the
lungs?
Beta-2
Activation of which adrenoceptor subtype has positive chronotropic and
inotropic cardiac effects?
Beta-1
Activation of which adrenoceptor subtype vasodilates blood vessels
supplying skeletal muscle?
Beta-2
Effect of activation of alpha adrenoceptors on visceral blood vessels on blood pressure?
Vasoconstricts increasing systemic blood pressure
Major adrenoceptors involved in increasing GLYCOGENOLYSIS (
breakdown of glycogen stored in the liver to release glucose)
Beta-2 and Alpha-1
Activation of beta-3 adrenoceptors on fat cells…
Increases lipolysis
Which adrenoceptor is important for the contraction of gastrointestinal and
urinary tract sphincters?
Alpha-1
Which adrenoceptors are important for secretions and motility along the
gastrointestinal tract?
Alpha-1, Alpha-2 & Beta-2
Relaxation of bladder muscle inhibits urination. Activation of which
adrenoceptor relaxes bladder muscle?
Beta-3
During late pregnancy activation of which adrenoceptor can relax the uterus
and delay childbirth?
Beta-2
Antagonism of alpha-1 adrenoceptors in the male reproductive system blocks…
Ejaculation
Sympathomimetic especially useful for cardiac resuscitation in patients renal
failure due to insufficient renal blood flow?
Dopamine
Beta-3 selective adrenergic agonist used to treat overactive bladder?
Mirabegron
Alpha-1 selective agonist used as a nasal decongestant?
Phenylephrine
Beta-1 selective agonist used to treat congestive heart failure?
Dobutamine
The major clinical use of norepinephrine is in the treatment of…
Severe hypotension
A patient presenting with severe anaphylactic shock would be treated with…
Epinephrine
Tocolysis is the prevention of labour contractions. Select a short-acting tocolytic drug that can be given to prevent premature labour?
Terbutaline, salbutamol
Beta-2 agonists used to treat asthma can also be used to treat pregnant patients presenting with…
Preterm labour
In presynaptic nerve terminals, noradrenaline is primarily broken down by…
Monoamine oxidase A
Noradrenergic synaptic signals are terminated by
Presynaptic uptake 1
Moclobemide is an MAO-A inhibitor. Clinically, moclobemide used as a/an…
Antidepressant
Moclobemide is a/an…
Reversible monoamine oxidase A (MAO-A) inhibitor indirect sympathomimetic antidepressant
Tricyclic antidepressants block…
Synaptic norepinephrine reuptake
Brimonidine is a/an…
Alpha-2 agonist used to treat glaucoma
In addition to reducing intraocular pressure, brimonidine is thought to help in
treatment in glaucoma because it…
Is neuroprotective
Which group of drugs is used to treat delay in initiating urination due to
benign prostatic hyperplasia?
Alpha-1 antagonists
Prazosin is used to treat
Chronic hypertension, urinary symptoms of benign prostatic hyperplasia (BPH)
Which group of drugs is used to treat delay in initiating urination due to
benign prostatic hyperplasia?
Alpha-1 antagonists
An elderly patient with benign prostatic hyperplasia has difficulty in initiating
urination. He could be prescribed…
Tamsulosin, prazosin, any other alpha-1 antagonists
Methyldopa results in the formation of methylnoradrenaline which is a…
False transmitter
Methyldopa is a competitive inhibitor of…
Tyrosine hydroxylase
What is the effect of an alpha-2 agonist acting g at presynaptic autoreceptors?
Decreased norepinephrine release
A rare but severe adverse effect of methyldopa, which increases the cost of treatment with methyldopa as it often requires monitoring?
Haemolytic anaemia
