Adrenergic and Cholinergic Receptors

Question 1

3 visceral tissues (visceral targets) the ANS controls

Answer 1

smooth muscle; cardiac muscle; glands

Question 2

pre-ganglionic fibres of the ANS (SNS and PNS) release this NT at the ganglia; the NT binds to this type of receptors

Answer 2

acetylcholine (ACh); nicotinic

Question 3

post-ganglionic fibres of the SNS release this NT at the ganglia; the NT binds to this type of receptors

Answer 3

norepinephine (NE); adrenergic

Question 4

post-ganglionic fibres of the PNS release this NT at the ganglia; the NT binds to this type of receptors

Answer 4

acetylcholine (ACh); muscarinic

Question 5

SNS nucleus is located in _____; ganglion in ______ axon varicosities in _________

Answer 5

nucleus in spinal cord; ganglia bilaterally adjacent to vertebral column; axons in target tissue

Question 6

PNS nucleus is located in _____; ganglion in ______ axon varicosities in _________

Answer 6

brainstem and medulla; ganglia in target tissue; axon in target tissue

Question 7

are nicotinic receptors ligand-gated ion channels or GPCRs

Answer 7

ligand-gated ion channels

Question 8

are adrenergic receptors ligand-gated ion channels or GPCRs

Answer 8

GPCRs

Question 9

are muscarinic receptors ligand-gated ion channels or GPCRs

Answer 9

GPCRs

Question 10

4 products of adrenal glands

Answer 10

mineralocorticoids, glucocorticoids, androgens, epinephrine and norepinephrine (remember salt, sugar, sex, stress)

Question 11

epinephrine has high affinity for which receptors

Answer 11

alpha and beta adrenergic receptors

Question 12

norepinephrine has high affinity for which receptors

Answer 12

alpha adrenergic receptors, weaker affinity for beta adrenergic receptors

Question 13

name 5 target tissues of SNS

Answer 13

eye (+ smooth muscle around eye), salivary glands, arterioles, lungs, heart, stomach, GIT, kidney, bladder

Question 14

name 5 target tissues of PNS

Answer 14

eye (+ lacrimal gland), salivary glands, lungs, heart, GIT, bladder, penis, prostate

Question 15

does the PNS directly affect vascular smooth muscle

Answer 15

no

Question 16

true or false: the heart has both sympathetic and parasympathetic innervation

Answer 16

true

Question 17

true or false: blood vessels have both sympathetic and parasympathetic innervation

Answer 17

false, only has sympathetic innovation (except in erectile tissue)

Question 18

name a major function of alpha 1 adrenergic receptor activation on the cardiovascular system

Answer 18

vasoconstriction

Question 19

name a major function of alpha 2 adrenergic receptor activation on the cardiovascular system

Answer 19

direct blood vessel effect of vasoconstriction at first, then presynaptic effect of vasodilation

Question 20

name a major function of beta 1 adrenergic receptor activation on the cardiovascular system

Answer 20

increased cardiac output

Question 21

name a major function of beta 2 adrenergic receptor activation on the cardiovascular system

Answer 21

vasodilation of skeletal muscle and heart; bronchodilation

Question 22

name a major function of muscarinic adrenergic receptor M2 activation on the cardiovascular system

Answer 22

decreased cardiac output

Question 23

name 4 physiological effects of parasympathetic overstimulation

Answer 23

diarrhea, urination, mitosis, bronchorrhea, bradycardia, emesis, lacrimation, lethargy, salivation, sweating

Question 24

Horner’s syndrome results from the loss of what

Answer 24

loss of sympathetic supply to head and neck

Question 25

drugs that act similarly to endogenous catecholamines (norepinephrine, epinephrine) are called

Answer 25

sympathomimetics or adrenergic agonists

Question 26

drugs that act similarly to acetylcholine are called

Answer 26

parasympathomimetics or cholinergics or cholinoreceptors stimulants

Question 27

name 2 irreversible acetylcholinesterase (ACh) inhibitors

Answer 27

organophosphates and sarin nerve gas

Question 28

this drug is a reversible inhibitor of acetylcholinesterase, so results in increased breakdown of Achieving at synaptic cleft, and is used to increase gut motility and myasthenia gravis

Answer 28

neostigmine (cholinergic)

Question 29

these 2 drugs are competitive muscarinic antagonists, dose-dependent, and are used for emergency treatment of arrhythmias, bronchodilators, ophthalmic exams

Answer 29

atropine and glycopyrrolate (anticholinergics)

Question 30

which drug crosses BBB to lesser extent and so has fewer CNS effects: atropine or glycopyrrolate

Answer 30

glycopyrrolate does not cross BBB as much so has fewer CNS effects

Question 31

this drug is only used in horses in Canada, has similar effects to atropine, and is used for gas/spasmodic colic, acute equine asthma treatment, and as rectal exams

Answer 31

N-butylscopolammonium bromide / hyoscine butyl bromide (anticholinergic)

Question 32

do alpha 2 agonists increase or decrease cardiac output

Answer 32

decrease cardiac output (so they are good premeds for anesthesia and standing procedures, since they are sedatives and analgesics, but they are bad for CV compromised patients)

Question 33

how do alpha 2 agonists provide sedation? provide anesthesia?

Answer 33

sedation due to inhibition or norepinephrine release in brainstem; anesthesia due to reduced NT release and signal transmission in afferent pathways

Question 34

how do alpha 2 agonists reduce cardiac output

Answer 34

initial vasoconstriction effect causes reflex bradycardia then presynaptic effects lead to subsequent vasodilation

Question 35

this alpha 2 agonist is a sedative used in healthy horses and ruminants and has side effects of AV block, reduced GI motility, sweating, increased myometrial tone

Answer 35

xylazine

Question 36

this alpha 2 agonist is 50-100x more potent than xylazine and is used mostly in horses for standing surgery

Answer 36

detomidine

Question 37

this alpha 2 agonist is used in SA sedation, dosed based in body surface area, makes over 50% of cats vomit. what is the drug? what is ir reversed with?

Answer 37

dexmedetomidine; reverse with atipamezole

Question 38

this beta 1 agonist is a positive ionotrope that does not increase heart rate, is given as CRI, and can cause seizures in cats

Answer 38

dobutamine

Question 39

this beta 2 agonist is a bronchodilator sometimes used to treat equine asthma, inhibits uterine tone, and is banned in food animals

Answer 39

clenbuterol

Question 40

this non-selective adrenergic agonist is used for emergency treatment of anaphylaxis or for CPR; sometimes added to local anaesthetics to cause vasoconstriction, increases cardiac output and myocardial oxygen consumption

Answer 40

epinephrine

Question 41

this alpha 1 antagonist reduces blood pressure, is used to treat functional urethral obstruction, and is 97% protein bound

Answer 41

prazosin

Question 42

this alpha 2 antagonist acts as a competitive inhibitor to revise sedation, cardiovascular effects, and analgesia associated with alpha 2 agonist administration

Answer 42

atipamezole