Autonomic Pharmacology Flashcards by Giselle Carter

what are 2 key roles of the autonomic nervous system

1) modulate contraction of smooth muscle
2) secretion from (endocrine and exocrine) glands

How well did you know this?

Not at all

Perfectly

where are the neural connections of the somatic vs the autonomic (PSNS and SNS) nervous systems

Somatic: in the CNS
Autonomic: in the PNS (PSNS - ganglia located close to the organ; SNS - ganglia located close to the spinal cord)

How well did you know this?

Not at all

Perfectly

in the autonomic nervous system, ganglia are located in (afferent/efferent) pathways

efferent

How well did you know this?

Not at all

Perfectly

the autonomic nervous system has (myelinated/unmyelinated) preganglionic neurons and (myelinated/unmyelinated) postganglionic neurons

myelinated; unmyelinated

How well did you know this?

Not at all

Perfectly

what are the 2 arms of the autonomic nervous system

PSNS and SNS

How well did you know this?

Not at all

Perfectly

what is the outflow of the sympathetic NS

thoracolumbar

How well did you know this?

Not at all

Perfectly

what is the outflow of the parasympathetic NS

craniosacral

How well did you know this?

Not at all

Perfectly

what is the ratio of pre to postganglionic neurons for the sympathetic ns? parasympathetic ns?

sympathetic: one pre to many post
parasympathetic: one pre to one post

How well did you know this?

Not at all

Perfectly

what is the distribution of RESPONSE and DISCHARGE for the sympathetic ns? parasympathetic ns?

sympathetic: generalized response, diffuse discharge
parasympathetic: limited response; discrete discharge

How well did you know this?

Not at all

Perfectly

T/F in general the SNS and PNS are physiological antagonists

How well did you know this?

Not at all

Perfectly

is the SNS or PNS essential for life

PNS

How well did you know this?

Not at all

Perfectly

what are 5 functions of the PNS:
1) pupillary ____________
2) _________ GI motility
3) __________ urination and defecation
4) __________ hr and bp
5) __________ absorption of nutrients

1) constriction
2) increased
3) increased
4) decreased
5) increased

How well did you know this?

Not at all

Perfectly

which branch of the autonomic nervous system is not essential for life

sympathetic nervous system

How well did you know this?

Not at all

Perfectly

what are the 6 functions of the SNS:
1) ________ heart rate and blood pressure
2) splenic ___________
3) ___________ of vessels in the skin
4) pupillary ____________
5) broncho___________
6) ________ blood glucose

1) increase
2) contraction
3) constriction
4) dilation
5) dilation
6) increase

How well did you know this?

Not at all

Perfectly

where are the sites of chemical transmission in the autonomic nervous system

1) between the pre and post-ganglionic neuron
2) between the post-ganglionic neuron and the target organ

How well did you know this?

Not at all

Perfectly

what are the 7 sites for pharmacological intervention in the PRESYNAPTIC neuron

1) action potential
2) synthesis of NT
3) storage of NT
4) metabolism of NT
5) release of NT
6) reuptake of NT
7) degradation of NT

How well did you know this?

Not at all

Perfectly

what are the 3 sites for pharmacological intervention in the POSTSYNAPTIC neuron

1) receptor binding
2) receptor stimulation (effectors)
3) response (secondary messengers)

How well did you know this?

Not at all

Perfectly

most drugs act via modifying actions on the pre or postsynaptic receptor

postsynaptic

How well did you know this?

Not at all

Perfectly

cholinergic neurons release

ACh

How well did you know this?

Not at all

Perfectly

all motor fibers to skeletal muscle use what NT at the neuromuscular junction

ACh

How well did you know this?

Not at all

Perfectly

what is the subdivision of cholinoreceptors

nicotinic (Nn and Nm) and muscarinic (M1-M5)

How well did you know this?

Not at all

Perfectly

what is the difference between Nn and Nm cholinoceptors

Nn: nicotinic neuronal (aka postganglionic)
Nm: nicotinic motor end plate (neuromuscular junction)

How well did you know this?

Not at all

Perfectly

adrenergic neurons release

catecholamines (dopamine, E, NE)

How well did you know this?

Not at all

Perfectly

the adrenal medulla releases primarily _________, and some _________

epinephrine; norepinephrine

How well did you know this?

Not at all

Perfectly

α1 and α2 adrenoceptors are involved in

contraction

describe the location of the following adrenoceptors: β1: β2: β3:

β1 - heart β2 - smooth muscle β3 - fat

all preganglionic neurons release the NT ______, which binds to ______ receptors on the postganglionic neuron

ACh; nicotinic (N)

what effectors have muscarinic ACh receptors for the PARASYMPATHETIC NS

cardiac and smooth muscle; gland cells; nerve terminals

what effectors have muscarinic ACh receptors for the SYMPATHETIC and PARASYMPATHETIC NS

sweat glands

what effector organs respond to dopamine as a NT from the SYMPATHETIC NS

renal vascular smooth muscle

what effector organs have α and β adrenergic receptors for NE from the SYMPATHETIC NS

gland cells; cardiac and smooth muscle

what type of ACh receptors exist at the gastrointestinal and genitourinary smooth muscle

what type of ACh receptors exist at the bronchiolar SM

what type of ACh receptors exist at the heart

what type of ACh receptors exist at the salivary gland

what type of ACh receptors exist at the eye

what type of ACh receptors exist at the autonomic nerve endings

what type of SNS receptors exist at the heart

β1

what type of SNS receptors exist on smooth muscle of the skin and splanchnic vessels

α1

what type of SNS receptors exist on smooth muscle of the skeletal muscle vessels

β2

what type of SNS receptors exist on splenic smooth muscle

α1

what type of SNS receptors exist at the bronchiolar SM

β2

what type of SNS receptors exist at the GI tract wall? GI tract sphincters

α2, β2; α1

what type of SNS receptors exist at the genitourinary tract SM of the: 1) bladder wall 2) sphincter 3) pregnant uterus

1) β2 2) α1 3) β2, α1

what type of SNS receptor exists at the penis and seminal vesicle smooth muscle

α1

what type of SNS receptor exists on salivary glands

α1

what type of SNS receptor exists on the eye muscles to cause: 1) contraction 2) relaxation

α1; β2

what type of SNS receptor exists at autonomic nerve endings

α2

adrenergic receptors alter

1) rate and force of contraction of the heart 2) tone of the blood vessels

what is the effect of α receptors on vascular smooth muscle

contraction: increased TPR -> increased BP -> reflex decrease in heart rate

what is the effect of β receptors on vascular smooth muscle

relaxation: decreased TPR -> decreased BR -> increased heart rate

Epinephrine: 1) what type of agonist/antagonist 2) what receptors activated

1) mixed α/β agonist 2) activates all α and β subtypes

What are the cardiac effects of epinephrine and why

increases rate (chronotropy) and force (ionotropy) of contraction via β1

What are the vascular smooth muscle effects of epinephrine and why

mainly vasoconstriction -> increased TPR via α1 some vasodilation -> decreased TPR via β2

By activating α1 receptors, what are some other effects of epinephrine

contraction of spleen, contraction of bladder sphincter, contraction of radial muscle of the iris causing mydriasis

By activating β2 receptors, what are some other effects of epinephrine

bronchodilation, decreased GI contractions, decreased uterine motility, relaxed bladder

How do drugs that stimulate α1 receptors cause the eyes to dilate

Contracting the radial muscle of the iris -> mydriasis

Clenbuterol: 1) what type of agonist/antagonist 2) what receptors activated

1) selective β agonist 2) β2

Terbutaline: 1) what type of agonist/antagonist 2) what receptors activated

1) selective β agonist 2) β2

Dobutamine: 1) what type of agonist/antagonist 2) what receptors activated

1) selective β agonist 2) β1

Phenylephrine: 1) what type of agonist/antagonist 2) what receptors activated

1) selective α agonist 2) α1

Isoproterenol: 1) what type of agonist/antagonist 2) what receptors activated

1) non-selective β agonist 2) β1/β2

What are the effects of clenbuterol/terbutaline and uses in the different species

bronchodilator cats: asthma dogs: chronic bronchitis horses: lower airway disease

Ractopamine: 1) what type of agonist/antagonist 2) what receptors activated

1) non-selective β agonist 2) mainly β1, some β2

What is the therapeutic use of ractopamine and in what species

growth promotion in cattle; increases lean muscle deposition

What is the main therapeutic use of dobutamine and why

cardiac support (CHF) -> improves contracility and bp without significant tachycardia

what is a consequence of dobutamine overdose

ventricular tachycardia and hypertension

what is the main use of isoproterenol and what is a benefit with this drug particularly

stimulates heart (heart block or bradycardia); β2 stimulation also results in decreased TPR and decreased BP

what are the main therapeutic uses of phenylephrine

1) vasoconstriction and increased BP (with reflex drop in heart rate possible) 2) BP support 3) pupillary dilation 4) nasal decongestion (because of constriction)

what is unique about dopamine

dose-dependent effects

Dopamine receptor stimulation and effect: 1) low doses 2) moderate doses 3) high doses

1) D1: dilates renal vasculature -> increased GFR 2) β1: increases contractility 3) α1: increases TPR -> increased BP

what are ephedrine, pseudoephedrine, and phenylpropanolamine

direct and indirect acting sympathomimetics -> activation of α and β and release of NE

what are the two main therapeutic uses of ephedrine and pseudoephedrine

1) decongestion 2) urinary tract incontinence

what is the main therapeutic use of phenylpropanolamine

urinary incontinence due to hypotonic urethra

what 2 adrenergic agonists can you give a patient with low BP or reduced blood flow (vascular hypotension) in the short-term

1) epinephrine 2) phenylephrine

what can you give a patient presenting with cardiac insufficiency (bradycardia, cardiogenic shock, CHF)

1) dopamine 2) dobutamine 3) epinephrine 4) isoproterenol

what can you use in combination to produce LOCAL vasoconstriction

epinephrine and lidocaine

what can you use to treat bronchoconstriction

1) clenbuterol (horse) 2) terbutaline (small animal) 3) epinephrine (respiratory issues associated with anaphylaxis)

what can you use to treat nasal congestion

1) phenylephrine 2) pseudoephedrine 3) ephedrine

what is the mainstay treatment of anaphylaxis (which causes both bronchospasm and cardiovascular collapse from vasodilation)

epinephrine

what can you use as a mydriatic to facilitate retinal examination

phenylephrine

phenoxybenzamine: 1) what type of agonist/antagonist 2) what receptors activated

1) non-selective α-antagonist 2) α1, a2

prazosin: 1) what type of agonist/antagonist 2) what receptors activated

1) selective α-antagonist 2) α1

atenolol: 1) what type of agonist/antagonist 2) what receptors activated

1) selective β-antagonist 2) β1

metoprolol: 1) what type of agonist/antagonist 2) what receptors activated

1) selective β antagonist 2) β1

proponalol: 1) what type of agonist/antagonist 2) what receptors activated

1) nonselective β antagonist 2) β1, β2

carvedilol: 1) what type of agonist/antagonist 2) what receptors activated

1) mixed adrenergic antagonist 2) β > α1

what are the therapeutic uses of phenoxybenzamine

1) diagnosis and treatment of pheochromocytoma 2) hypertonic urethra

what is a major adverse effect of phenoxybenzamine and an important therapeutic consideration

can cause severe hypotension (blocking α1) -> do not want to give epinephrine to reverse because the α receptors are blocked, so only the β effects of epinephrine will remain -> can get even further hypotension

what are the therapeutic uses of prazosin

hypertonic urethra due to functional obstruction; can be used to help treat CHF

in regards to β antagonists, drugs with higher affinity for what receptor are more useful clinically

β1

β antagonists are used for what 2 diseases

1) cardiovascular 2) ocular

what is the therapeutic use of propanolol

supraventricular and ventricular tachyarrhythmias, thyrotoxicosis for cats with hyperthyroidism, pheochromocytoma, HCM in cats

what β antagonist has minimal hepatic first pass effects

atenolol

what are the therapeutic uses of atenolol and metoprolol

same as propanolol BUT they have reduced adverse effects like bronchospasm

what are the therapeutic usees of carvedilol

cardiomyopathy in dogs, free-radical scavenger

bethanechol: 1) what type of agonist/antagonist 2) what receptors activated

1) cholinergic agonist 2) muscarinic

what is the therapeutic use of bethanechol

stimulates urinary bladder -> hypocontractile bladder

when is bethanechol contraindicated

GI or urinary obstruction

what is a possible side effect of bethanechol and what is the antidote

salivation, lacrimation, urination, defacation; atropine (muscarinic blocker)

what are the therapeutic uses of pilocarpine

pupillary constriction (miosis) and tear production

what is the mechanism of action of edrophonium and what are 2 key factors about it

prolongs half life of ACh by binding to the active site of acetylcholinesterase; short duration of action and poor penetration into the CNS

what is the mechanism of action of neostigmine/pyridostigmine and what are 2 key factors

carbamylates active site of acetylcholinesterase; longer duration of action than edrophonium and poor penetration into CNS

what are the therapeutic uses of edrophonium/neostigmine/pyridostigmine

intestinal motility disorders (ex. paralytic ileus)

what are the 2 classes of non-selective muscarinic cholinergic antagonists

tertiary amides, quaternary ammonium compounds

what cholinergic antagonists are tertiary amides

atropine, oxybutynin tropicamide

what cholinergic antagonists are quaternary ammonium compounds

propantheline, ipratropium, hyoscine

what are the therapeutic uses of atropine

mydriasis (pupil dilation) and reduced ciliary spasms (uveitis), treating organophosphate poisoning, bradyarrhythmias

what are the therapeutic uses of tropicamide

pupil dilation (mydriasis)

what are some possible adverse effects of oxybutynin

constipation and urine retention

what are the therapeutic uses of oxybutynin and what is a general caution

spastic bladder; do not use if bladder or GI obstruction or if there is an infection

do tertiary amines or quaternary ammoniums have more CNS effects

tertiary amines

what are the therapeutic uses of propantheline

GI motility disorders, spastic bladder

what are the therapeutic uses of ipratropium

bronchospasm associated with respiratory disorders

what are the therapeutic uses of hyoscine and what is a potential adverse effect

GI motility disorders; can cause tachycardia and reduced GI motility

what is a potential use of hyoscine

acute severe exacerbations of airway obstruction in horses -> it causes immediate bronchodilation