Peripheral Nervous System Flashcards
What does the central nervous system consist of?
The brain and the spine
What does the peripheral nervous system consist of?
Everything that’s not the brain and spine
What is another name for sensory?
Afferent
What is included in the sensory?
- Sight
- Touch
- Hearing
- Tast
- Smell
What are the divisions of the peripheral nervous system?
- Motor
- Splits in to autonomic and somatic
- Autonomic splits into: Parasympathetic and sympathetic and enteric
What is another name for motor?
Efferent
What is the somatic effectors?
Skeletal muscles
Is the somatic response voluntary or involuntary?
Voluntary
Is the automatic response voluntary or involuntary?
Involuntary
What are the effectors involved in the automatic response?
Cardiac muscle/smooth muscle/exocrine glands/some endocrine glands/adipose tissue
What is the phrase used to explain the parasympathetic nervous system?
Rest and digest
What is the phrase used to explain the sympathetic nervous system?
Fight and flight
What are the effector for enteric?
Gastrointestinal tract
How many pairs of cranial nerves do we have in the brain?
12 pairs
What are the 12 pairs of cranial nerves?
- Olfactory
- Optic
- Trigeminal
- Facial
- Glossopharyngeal
- Vagus
- Accessory
- Hypoglossal
- Vestibulocochlear
- Abducens
- Trochlear
- Oculomotor
What are the intermediate nerve for sensory?
Soft palate and anterior tongue
What are the intermediate nerve for motor?
Sublingual and submaxillary gland
What type of nerve is olfactory?
Sensory - smell
What type of nerve is optic?
Sensory - sight
What type of nerve is trigeminal?
Sensory - face, sinuses and teeth
Motor - muscles of mastication
What type of nerve is facial?
Motor - muscle of the face
What type of nerve is glossopharyngeal?
Sensory - tonsil, pharynx, posterior tongue
Motor - Pharyngeal musculature
What type of nerve is vagus?
Sensory - Heart, lungs, bronchi, trachea, larynx, pharynx, GI tract, external ear
Motor - heart, lungs, bronchi, GI tract
What type of nerve is accessory?
Motor - sternocleidomastoid and trapezium muscles
What type of never is hypoglossal?
Motor - muscle of the tongue
What type of nerve is vestibulocohlear?
Sensory - inner ear
What type of nerve is abducens?
Motor - external rectus muscle
What type of nerve is trochlear?
Motor - Superior oblique muscle
What type of nerve is oculomotor?
All eye muscles expect for external rectus and superior oblique muscles
How many pairs of spinal nerves are there?
31 pairs
How is the spine split up?
- Brainstem
- Cervical
- Thoracic
- Lumbar
- Sacral
What are the sections in the brainstem?
iii,
vii,
ix,
x
What are the sections in the cervical?
C1, C2, C3, C4, C5, C6, C7, C8
What are the sections in the thoracic?
T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12
What are the sections in the lumbar?
L1, L2, L3, L4, L5
What are the sections in the sacral?
S1, S2, S3, S4, S5
What is the ganglion?
Cluster of neural bodies outside of the CNS
What are examples of sensory ganglia?
Dorsal root ganglion
Cranial nerves
What are examples of autonomic ganglia?
Sympathetic chain ganglia
Terminal ganglia
What are preganglionic neurones?
Neurons from brain stem and spinal neurones
What happens in the autonomic nervous system?
- Axon extends to and synapses with cell of 2nd neurones that lies in ganglion
- Axon of this neurones or postganglionic fibre supplies effector cells
What are the preganglionic neurons like in parasympathetic nervous system?
Long
What are the postganglionic neurons like in parasympathetic nervous system?
short
What are the preganglionic neurons like in sympathetic nervous system?
Short
What are the postganglionic neurons like in sympathetic nervous system?
Long
What is meant by a two neural chain?
preganglionic to postganglionic fibre
What are the sympathetic nerve fibre?
Lateral horn of thoracic/lumbar
What are the parasympathetic nerve fibre?
cranial/sacral areas of CNS
Where are myelin in peripheral nervous system derived from?
Schwann cells
Where are myelin in the central nervous system derived from?
Oligodendrocytes
Where can you find varicosity?
At the ends of postganglionic fibres
What is varicosity?
Swelling at the end of post ganglionic fibre which release neurotransmitters
What are telodendria?
Pearl like structures with varicosity (contains neurotransmitter)
What are the two main receptors in the parasympathetic and sympathetic nervous system?
GPCR and ligand-gated ion channels
What type of receptor is an ionotropic receptor?
Ligand-gated receptor
What type of receptor is a metabotropic receptor?
GPCR
Which has a fast synaptic transmission ionotropic or metabotropic receptors?
Ionotropic receptord
What is the postsynaptic receptor of the ionotropic receptor directly link to?
Ion channels
Is there direct excitation or inhibition in metabotropic receptors?
No
How does a ionotropic receptors work?
Na+ channels opened causing membrane depolarisation, excitatory neurotransmission
How does metabotropic receptors work?
Postsynaptic receptors signals to channel proteins via G-protein via intracellular 2nd messengers
What response does metabotropic receptors cause?
- Alter transcription factor
- Alter electrical activity
- Stimulate secreation
What response does inotropic receptors cause?
K+ or Cl- channels are opened causing hyperpolarisation, inhibitory neurotransmission
What is the receptor for acetylcholine?
Cholinergic receptor
What are the two types of cholinergic receptors?
- Nicotinic-ACh receptors
- Muscarinic-ACh receptors
Does nicotinic-ACh receptors cause excitatory or inhibitory effect?
Exitatory
What are the effectors to nicotinic-ACh receptors?
- Skeletal muscles
- Ganglion
- CNS
Does muscarinic-ACh receptors cause excitatory or inhibitory effect?
Both
What are the effectors to muscarinic-ACh receptors?
- Smooth muscle
- Cardiac muscle
- Glands
What type of receptor is muscarinic-ACh receptors?
Ligand-gated ion channels (Ionotropic)
What type of receptor is nicotinic-ACh receptors?
GPCR (metabotropic)
What domains do muscarinic-ACh receptors have?
Extracellular, transmembrane and intercellular
What domains do nicotinic-ACh receptors have?
2 binding domains for ACh
What receptors are for noradrenaline?
Adrenergic receptors
What are the subclassifications for adrenergic receptors?
a1, a2, B1, B2, B3
What is the result of a1 adrenergic receptor?
Sympathetic target tissue
What is the result of a2 adrenergic receptor?
digestive organ, platelets and nerver terminals
What is the result of B1 adrenergic receptor?
Heart, salivary glands
What is the result of B2 adrenergic receptor?
Smooth, skeletal, nerve terminal and mast cells
What is the result of B3 adrenergic receptor?
Skeletal, adipose, gallbladder, urinary bladder
Is a1 adrenergic receptor excitatory or inhibitory?
Excitatory
Is a2 adrenergic receptor excitatory or inhibitory?
inhibitory
Is B1 adrenergic receptor excitatory or inhibitory?
Excitatory
Is B2 adrenergic receptor excitatory or inhibitory?
Inhibitory
What type of receptor is adrenergic receptor?
GPCR
What does B1,B2,B3 adrenergic receptors do?
Activates adenylyl cyclase - increases cAMP (they have different consequences: constriction or relaxation)
What does a1 adrenergic receptors do?
Activates phospholipase C, leading to inositol triphosphate (IP3) and diacylglycerol - increase in Ca2+ smooth muscle contraction
What does a2 adrenergic receptors do?
Inhibits adenylyl cyclase, leading to reduced cAMP
What do sympathetic postganglionic fibres usually release?
Noradrenaline
What does sympathetic postganglionic fibres release in the sweat glands?
acetylcholine
What happens if there is no neurotransmission of noradrenalin or acetylcholine?
- Use chemical mediators instead
- E.G ATP recreated to blood vessels to cause vasocontriction
Can some neurons have more than one neurotransmitter?
Yes
What is the sympathetic effects of stimulation of arrestor pill muscles?
-Contraction, erection of hairs (a1)
What is the parasympathetic effects of stimulation of arrestor pill muscles?
None
What is the sympathetic effects of stimulation of sweat glands?
Secretion: palm and soles (a1), generalised (cholinergic)
What is the parasympathetic effects of stimulation of sweat glands?
None
What is the sympathetic effects of stimulation of lacrimal glands?
None
What is the parasympathetic effects of stimulation of lacrimal glands?
Secretion
What is the sympathetic effects of stimulation of eye?
Pupil dilation (a1) accommodation distance (B2)
What is the parasympathetic effects of stimulation of eye?
Pupil constriction
Accommodation close
What is the sympathetic effects of stimulation of blood vessels to skin?
Dilation (ACh); constriction (a1)
What is the parasympathetic effects of stimulation of blood vessels to skin?
None
What is the sympathetic effects of stimulation of blood vessels to skeletal muscles?
Dilation (B2, cholinergic, nitroxinergic)
What is the parasympathetic effects of stimulation of blood vessels to skeletal muscles?
None
What is the sympathetic effects of stimulation of blood vessels to heart?
Dilation (B2), constriction (a1, a2)
What is the parasympathetic effects of stimulation of blood vessels to heart?
None
What is the sympathetic effects of stimulation of blood vessels to lungs?
Dilation (B2); constriction (a2)
What is the parasympathetic effects of stimulation of blood vessels to lungs?
None
What is the sympathetic effects of stimulation of blood vessels to kidney?
Dilation (increase urine production B1/B2) Constriction (decrease urine production a1/a2)
What is the parasympathetic effects of stimulation of blood vessels to kidney?
None
What is the sympathetic effects of stimulation of blood vessels to brain?
Dilation (cholinergic and nitroxidergic)
What is the parasympathetic effects of stimulation of blood vessels to brain?
None
What is the sympathetic effects of stimulation of veins?
Constriction (Decrease urine production a1/B2)
What is the parasympathetic effects of stimulation of veins?
None
What is the sympathetic effects of stimulation of heart?
Increase heart rate, contractile force, BP (a1,B1)
What is the parasympathetic effects of stimulation of heart?
Decrease heart rate, contractile force, BP
Finish the sentence:
Both the parasympathetic and sympathetic division of autonomic nervous system, acetylcholine is released by….
preganglionic fibres
Finish the sentence:
Both the parasympathetic and sympathetic division of autonomic nervous system, acetylcholine is released by preganglionic fibres and interact with…
nicotinic Ach receptors at ganglion
What happens when the bladder is not full relating to the peripheral nervous system?
Sympathetic nervous system causes bladder to relax and internal urethral sphincter closes
What happens when the bladder is full relating to the peripheral nervous system?
Parasympathetic nervous system causes bladder to contract and internal urethral sphincter relax
What hormone is released and what is its’ bind receptors in the parasympathetic?
Acetylcholine with muscarinic receptor
What hormone is released and what is its’ bind receptors in the sympathetic?
Noradrenaline with adrenergic receptors