The Autonomic Nervous System Flashcards
what structures does the autonomic nervous system include?
visceral structures
glandular myoepithelium
fat
vasculature
what type of system is the autonomic nervous system?
it is a diffuse system and is innervating
what are the components of the ANS?
it has afferent, central and efferent components
afferent + efferent nerves often use same pathways
afferent visceral axons may also travel via somatic spinal nerves to reach the CNS
when talking about the ANS, what are we talking about generally?
general visceral efferent innervations
sympathetic nervous system aka?
fight or flight
thoracolumbar region contain nerves for this region
parasympathetic nervous system aka?
rest and digest
cranio-sacral region contain nerves for this system
how many nerves from spinal cord to muscle? for somatic nervous system
one
how many nerves from spinal cord to muscle for ANS?
2 nerves
first nerve compared to second nerve? for ANS (nerves from spinal cord to muscle)
first is really short
second is really long apart from adrenal glands
what does the adrenal gland pump out?
epinephrine (adrenaline)
asthma opening up airways you can either?
stimulate sympathetic nervous system or block parasympathetic nervous system
what do neurotransmitters activate in dual innervation?
activate different G protein-coupled receptors
where are the main control centres for the ANS?
these are located in the hypothalamus
what part of the hypothalamus influences the parasympathetic nervous system?
rostral hypothalamus influences it
what part of the hypothalamus influences the sympathetic nervous system?
caudal hypothalamus influences sympathetic nervous system
other parts of the CNS can influence the control centres - give e.g.’s
cerebrum and limbic system (e.g. fear causing piloerection)
olfactory stimulation causing drooling
where do sympathetic pathways originate from?
from lateral/intermediate horn of the thoracolumbar spinal cord
and they leave spinal cord via ventral roots of T1 to L3/L4
where do the nerves of the parasympathetic nervous system originate from?
from the brainstem and sacral segments of the spinal cord
where is synapse in ganglia located?
it is located close to or within target organ therefore generally long presynaptic and short postsynaptic neurones
where does the vagus nerve go?
it starts in brainstem and reaches as far as the colon
from 23 onwards
what is the enteric nervous system?
it refers to autonomic neurones that collectively innervate the alimentary tract (where they reside)
where are autonomic nerves found?
found in two locations:
The submucosal (Meisner) plexus is located within the submucosa
The myenteric (Auerbach) plexus is found between circular & longitudinal muscle coats
