SARs In The Peripheral Nervous System Flashcards
What is the PNS comprised of?
The somatic efferent system - inner gates skeletal muscle. VOLUNTARY
Autonomic system - inner gates smooth muscle. INVOLUNTARY
What is the autonomic system comprised of?
Sympathetic and parasympathetic systems
What’s the difference in signal speed between the sympathetic and parasympathetic nervous system?
Parasympathetic signals go straight from the CNS to the tissue - much faster
Sympathetic signals go to a sympathetic chain and THEN to the tissues - much slower
Why’re ganglions significant?
As there is a break, neurological synapse, which requires neurotransmitters
This can be manipulated with drugs, blocking or increasing selectivity
What’s the structure of acetylcholine?
What’s the structure of noradrenaline?
Where does the sympathetic nervous system typically gather signals from the CNS?
Thoracic and Lumbar regions
Where does the parasympathetic nervous system typically gather signals from the CNS?
Medulla and sacral regions
What does somatic mean?
Voluntary
What neurotransmitter is at the sacral ganglion?
ACh
What neurotransmitter is at the medulla ganglion?
ACh, then ACh again
What neurotransmitter is at the cervical ganglion?
ACh, then nor adrenaline after sympathetic chain
What neurotransmitter is at the thoracic ganglion?
ACh, then dopamine after sympathetic chain
What neurotransmitter is at the lumbar ganglion?
ACh, then ACh again
What’re the predominant receptors for ACh in the sympathetic and parasympathetic systems?
Nicotinic, in both systems
What’re the receptors present at the tissue for the medulla and lumbar regions of the parasympathetic nervous system?
Muscarinic, both activated by ACh
What’re the receptors present at the tissue for the cervic region of the sympathetic nervous system?
Adrenoreceptors - alpha and ß
What’re the receptors present at the tissue for the thoracic region of the sympathetic nervous system?
Dopamine receptors
What’s characteristic of the somatic nervous system?
No ganglia break, one single neuron all the way to the muscle
ACh is the neurotransmitter
ACh acts on nicotinic receptors located on skeletal muscle membranes
What are nicotinic receptors linked to on skeletal muscle membranes?
Nicotinic receptors are linked to a Na+ ion channel on muscles
What’s the diffference between the length of the pre and post neuron in the sympathetic and parasympathetic nervous systems?
Parasympathetic - long pre-ganglionic nerve, short post-ganglionic nerve
Sympathetic - short pre-ganglionic nerve, long post-ganglionic nerve
BOTH pre-ganglionic nerves release ACh to act on nicotinic receptors on the post-ganglionic nerve
What are 3 agonists at nicotinic receptors?
ACh, nicotine and carbachol
What are 3 antagonists at nicotinic receptors?
d-tubocurarine - paralyses muscle
Pancuronium
Suxamethonium - ganglion blocker
What system does the term ‘rest and digest’ refer to?
The parasympathetic system
What system does the term ‘fight or flight’ refer to?
Sympathetic system
