Cholinergic and Adrenergic Pharmacology Flashcards
Is cholinergic parasympathetic or sympathetic?
Parasympathetic
Is adrenergic parasympathetic or sympathetic?
Sympathetic
What is adrenergic and cholinergic pharmacology responsible for?
● Control of blood pressure: raise it in shock, lower it in hypertension
● Control of heart rate; speed up lethal bradycardias, slow down dangerous tachycardias
● Anaesthetic agents; muscle relaxants
● Regulation of airway tone; treat life threatening bronchospasm
● Pressures in the eye; prevent glaucoma causing blindness
● Control of GI function; diarrhoea and constipation
How many neurones innervate muscles in somatic nervous system?
1 neurone
How many neurones innervate muscles in autonomic nervous system?
2: Pre and post ganglionic fibres
What’s the difference between sympathetic and parasympathetic ganglia?
- The parasympathetic ganglia are near their targets with short post-ganglionic
nerves - Sympathetic are near the spinal cord with longer post-
ganglionic fibres
What makes up the parasympathetic NS?
● Cranial nerves like the oculomotor nerve, facial nerve and vagus nerve carry signals to the body
● A further sacral outflow innervates the pelvis
What type of receptor does the parasympathetic NS work on?
- Short post-synaptic nerve fibres reach the targets and release acetylcholine (ACh)
- acts on muscarinic receptors of various subtypes
What does the sympathetic NS consist of?
● Regulates the fight-and-flight response
● Nerve fibres originating in the spinal cord terminate in ganglia near the cord, then
send out long nerve fibres to blood vessels, muscles etc.
What type of receptor does the sympathetic NS work on?
They release noradrenaline which activates adrenergic receptors, of which there are two main types (alpha/ beta) with subtypes
Which type of receptor do both parasympathetic and sympathetic NS work on?
Parasympathetic and sympathetic fibres coming out of the CNS both release ACh, which acts on specific receptors called nicotinic receptors
As mediators
As a mediator, what do post ganglionic parasympathetic fibres release more of?
more acetylcholine, this time
acting on muscarinic receptors
As a mediator what do post-ganglionic sympathetic fibres release?
release noradrenaline, acting on alpha and beta adrenoceptors
What type of receptors are muscarinic receptors?
GPCRs
How many muscarinic receptor types are there?
M1-5
Where is M1 mainly?
In the brain
Where is M2 mainly?
In the heart (activation slows heart)
Where is M3 mainly?
glandular and smooth muscle (cause bronchoconstriction, sweating, salivary gland secretion)
Where is M4/5 mainly?
In CNS
What are some anti cholinergic drug side effects?
● In the brain, anticholinergics worsen memory and may cause confusion
● Peripherally, may get constipation, drying of the mouth, blurring of the vision, worsening of glaucoma
What do alpha agonists do?
● Alpha 1 activation causes vasoconstriction, particularly in the skin and splanchnic beds: less so in brain, lung, heart
● Adrenaline will raise blood pressure and cardiac work in other settings
● Topical alpha activation in nasal decongestion
What do alpha 1 activators do?
raise blood pressure
What do alpha 2 activators do?
lower blood pressure
What do alpha blockers do?
Block alpha 1 to lower blood pressure
