Autonomic nervous system Flashcards
How does the autonomic motor system act on smooth muscles of the body?
Stimulates the muscles based on coordination from CNS
How does the autonomic motor system act on secretory glands?
Causes increased secretion from the glands
Which factors can activate the autonomiscsensory system?
Chemoreceptors become activated
Baroreceptors become activated (pressure)
Tension and distension
How are the sympathetic and parasympathetic systems differenciated?
Sympathetic has short pre-ganglionic fibres and long post-ganglionic fibres
Parasympathetic has long pre-ganglionic fibres and short post-ganglionic fibres
Where do the sympathetic pre-ganglionic neurones originate?
Between T1 and L2 of the spinal column (lateral horn and migrate ventrally)
Where to the parasympathetic pre-ganglionic neurones originate?
Brainstem or S2-4 of spinal cord
Where are the cell bodies located for sympathetic and parasympathetic?
Sympathetic - Sympathetic chain or other named ganglia close to the spinal cord
Parasympathetic - On the target organ usually
Which cranial nerves are most used in the parasympathetic system?
3 - Oculomotor (iris contraction/dilation)
7 - Facial nerve (Tear production)
9 - Glossopharyngeal nerve (Salivary gland)
10 - Vagus nerve 1 - Larynx pharynx and heart. 2 - Lungs, pancreas, GI Tract and heart
What does the spinal cord section of the parasympathetic system control?
Colon, unirary bladder, sex organs
What are 2 pathologies associated with ANS disfunction?
Postural hypotension - Disruption of sympathetic nerves of blood vessels causing dizziness, lightheadedness and faintness
Horner’s syndrome - Interruption of nerves supplying eye causing drooping of upper eyelid, constriction of pupil and loss of sweating (on 1 side of face)
