Autonomic Central Nervous Pharmacology Flashcards
What are the two divisions of the autonomic nervous system?
Sympathetic nervous system and parasympathetic nervous system
What neurotransmitter is released by preganglionic neurons in both SNS and PNS?
Acetylcholine (ACh)
What type of receptors do preganglionic neurons of ANS act on?
Nicotinic acetyl choline receptors (nAChRs)
What is the main neurotransmitter released by postganglionic sympathetic neurons?
Noradrenaline (except in sweat glands)
What type of neurotransmitter do postganglionic parasympathetic neurons release?
Acetylcholine
What type of receptors do parasympathetic postganglionic neurons act on?
Muscarinic acetylcholine receptors (M1-M5)
What are the effects of activating beta1 adrenergic receptors?
Increases heart rate and force of contraction
What are the effects of beta2 receptor activation ?
Brochodilation and vasodilation in skeletal muscles
What is the main effect of alpha1 adrenergic receptor activation?
Vasoconstriction and blood pressure increase
What is the effect of alpha2 adrenergic receptor activation?
Inhibits neurotransmitter release (presynaptic inhibition)
What drug is a muscarinic antagonist used to increase heart rate?
Atropine
What are the clinical uses of beta blockers
Treat hypertension angina
What drug is a selective beta2 agonist used for asthma?
Salbutamol
What drug is a selective alpha1 agonist used for nasal congestion?
Phenylephrine
What type of receptors mediate the parasympathetic effect on the heart?
M2 muscarinic receptors
What is the mechanism of action of ganglion blockers like hexamethonium
Block nicotinic receptors in autonomic ganglia, inhibiting both SNS and PNS
How does cocaine affect sympathetic neurotransmission?
Blocks noradrenaline trip take increasing sympathetic activity
What is effect of Alpha methyl tyrosine?
Inhibits catecholamine synthesis reducing sympathetic activity
What effect does atropine have on the eye?
Causes pupil dilation by blocking M3 receptors
What drug blocks dopamine conversion and is used in Parkinson’s?
Carbidopa
What’s clinical use of clonidine?
Treats hypertension by stimulating alpha 2 receptors to reduce sympathetic outflow
What is the effect of prazosin
Alpha antagonist that causes vasodilation and lowers blood pressure
What enzyme metabolises noradrenaline in the synapse
Monoamine oxidase (MAO)
What receptor is responsible for sweat gland stimulation by the sympathetic nervous system
M3 muscarinic receptors
What is the significance of receptor subtype selectivity in drug development?
More selective drugs have fewer side effects and improved safety
