Autonomic Pharmacology Flashcards
What part of the spinal cord does the sympathetic nervous system arise from
Thoracolumbar segment
Where does the parasympathetic nervous system arise from on the spinal cord
Cranio scarial segment
What does the SNS do at the liver
Increase conversion of glycogen to glucose
What does the SNS do at the kidney
Decreased urine secretion
What does the PNS do at the kidney
Increased urine secretion
What does the SNS do to the adrenal medulla
Increase adrenaline and noradrenaline (catecholamines) secretion
Does the PNS have an effect on the adrenal medulla
No because adrenal medulla releases adrenaline or noradrenaline so it is classed into the SNS
What effect does the SNS have on the lung
Bronchial is relaxed
What does the parasympathetic NS secrete as neurotransmitters
Acetylcholine
What does the SNS neurone release as neurotransmitters
Ach and catecholamines
What is the length of the pre-ganglionic neurone of the SNS and PNS
PNS= longer SNS= shorter
What receptors does acetycholine of both SNS and PNS work on the pre-ganglionic neurone
Nicotinic receptors
What receptor does the acetycholine act on the effector in the PNS
Muscarinic receptors
What type of receptors are muscarinic receptors
GCPRs
What type of receptors does catecholamines act on the effector organ in the SNS
Alpha or beta adrenoceptors
What receptor does adrenaline act on
Beta adrenoceptor
What type of receptor does noradrenaline act on
Alpha adrenoceptor
What are the three layers of the adrenal cortex and what type of hormone do they release
Zona glomerulosa: mineralocorticoid
Zona fasiculata: glucocorticoid
Zona reticularis: adrenal androgens
How is acetylcholine released
- AP occurs at the pre-ganglionic neurone
- voltage- gated calcium channels open
- exocytosis occurs
- acetycholine binds to nachrs
- acetycholine is brocken down by acetycholinesterase
- choline is transported back into the pre-synaptic neurone
- choline is converted to acetycholine and stored back into vesicles
How many units does nicotinic receptors have
5 subunits
What type of receptor is nicotinic achrs
Ligand- gated ion channels
What are the subunit types of the alpha receptor
- alpha
- gamma
- beta
How are nicotinic receptors different with their location
According to the location nicotinic receptors vary in their alpha subunit
Name a drug that will target the nicotinic receptors in the ganglia but not the nicotinic receptors at the NMJ
Hexamethonium
What type of antagonist is hexamethonium
Non-competitive
What autonomic division does hexamethonium block
All of the autonomic system
Where are muscarinic receptors found
On effectors (smooth, cardiac, secretory glands) of the PNS
How many transmembrane segments does muscarinic receptors have
7
How many subtypes does muscarinic receptors have
5
What type of receptor is muscarinic receptors
GCPRs
Name a muscarinic receptor antagonist
Atropine
What type of antagonist is atropine
Competitive
Name an agonist of muscarinic receptors
Ach and muscarine (from mushrooms)
What are parasympathomimetics
Drugs that mimic the effects of PNS activation
What are the effects of parasympathomimetics
- cardiovascular: decreased heart rate
- smooth muscle: contracts
- exocrine glands: increase in sweating, salivation and bronchial secretion
Why is bronchial secretion bad for the body
It narrows the airways and leads to respiratory failure
What is the treatment of muscarine poisoning
Atropine (antagonist)
What are the clinical agonist of muscarinic receptors
Pilocarpine
What is pilocarpine used to treat
Glaucoma
What is the route of administration of pilocarpine
Topical (eye drop) to the eye
What subtype of muscarinic receptor does pilocarpine act on
M3 on ciliary muscles of the eye
Where is M1 receptor located
Stomach and salivary glands
Where is M2 receptor located
Cardiac muscle
Where is M3 receptors located
Smooth muscle
Is atropine a specific or less specific antagonist
Less specific
What are the clinical uses of muscarinic antagonist
Asthma Treat bradycardia During operations to decrease secretions Dilate pupils Urinary incontinence Motion sickness
How many sub types does adrenoceptors have
5 subtypes
What are the 5 subtypes of the adrenoceptors
Alpha : 1 and 2
Beta : 1, 2,3
Where is alpha 1 adrenoceptors located
Smooth muscle
Blood vessels
Where are alpha 2 adrenoceptors located
Nerve terminals
Where are beta 1 adrenoceptors located
Heart (you have one heart and beta one)
Where are beta 2 adrenoceptors located
Lungs ( 2 lungs for beta 2)
Where are beta 3 adrenoceptors located
Fat and bladder
What are the clinical uses of alpha adrenoceptors agonist
- alpha 1: vasoconstriction on blood vessel with local anaesthetics
- alpha 1: nasal decongestant
- alpha 2: hypertension
- alpha 2: fascial erythema in rosacea
Name an agonist that is used with local anaesthetics for vasoconstriction of blood vessel
Adrenaline and noradrenaline
Name an agonist that is used for nasal decongestants
Phenylephrine
Name an agonist used for fascial erythema in rosacea
Brimonidine
What type of receptors is alpha 1 adrenoceptor
GCPRs
Why is the g-protein of alpha 1 adrenoceptors
Gq
What does Gq protein do when activated by an agonist binding to alpha 1 adrenoceptors
Activates phospholipase c
Phospholipase C hydrolysis PIP2 into DAG and IP3
IP3 regulates calcium
What is the G protein of alpha 2 adrenoceptors
Gi
What does Gi protein do
Inhibit adenyly cyclase so there is reduced levels of CAMP
What G-protein does all of beta adrenoceptors have
Gs
What does Gs protein do
Stimulate adenyl cyclase which increases CAMP
What g-protein does muscarinc 1 and 3 receptor have
Gq
What type of g-protein does muscarinic 2 receptors have
Gi
What are the uses of alpha antagonist
- hypertension
- benign prostatic hyperplasia
Alpha adrenoceptor antagonist used to treat hypertension
Doxazosin
Alpha adrenoceptor antagonist used to treat benign prostatic hyperplasia
Tamsulosin
What are the uses of beats adrenoceptor agonist
- cardiogenic shock
- anaphylactic shock
- asthma
Name an agonist used for cardiogenic shock
Adrenaline, dolbutamine
Agonist used for anaphylactic shock
Adrenaline
Agonist used to treat asthma
Solbutamol
What are the main uses of beta adrenoceptor antagonist
- angina
- cardiac arrhythmia
- hypertension
- heart failure
How is noradrenaline synthesis, release and recycling inhibited
- inhibiting uptake 1 by noradrenaline transporter which brings NAd back into the varicosity
- inhibit monoamine oxidase which breaks down noradrenaline or dopamine
- indirectly acting sympathetic amines: structurally related to NAd which are substrates of noradrenaline transporter and vesicular monoamine transporter and displace NAd
Name a drug that inhibit noradrenaline transporter
Cocaine
Name an indirectly acting sympathetic amine
Amfetamine
Ephedrine
