Autonomic Nervous System Flashcards
Nervous System
a highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body.
Peripheral Nervous System
PNS
nervous system that itsn’t brain and spinal cord
contains autonomic nervous system
Motor Efferents
motor neurons
Autonomic Motor Neurons
Motor neurons that move without our own input
Somatic Motor Neurons
Voluntary motor neurons
Sympathetic Nervous System
SANS
best known for fight or flight
dilates pupils, inhibits salvation, relaxes airways, constrict blood vessels, accelerates heartbeat, stimulate sweat production, stimulates glucose production, stimulates secretion of norepinephrine and epinephrine, inhibits voiding(pooping), stimulates ejaculation, stimulates orgasm, piloerection
Enteric Nervous System
ENS
intestinal walls, helps to digest food via peristalsis
Parasympathetic Nervous System
PANS
best known for rest and digest
constricts pupils, stimulates salivation, constricts airways, slows heartbeat, stimulates bile release and digestion, stimulates secretion, promotes voiding, and stimulates erection.
Organisation of SANS
Has segmental chain ganglia due to somites
no axons from brain or cervical/sacral spinal cord (all centre based)
three midline ganglia
short preganglionic and long post ganglionic nerves
Ganglion
a group of neuron cell bodies
Somites
precursor populations of cells that give rise to important structures associated with the vertebrate body plan and will eventually differentiate into dermis, skeletal muscle, cartilage, tendons, and vertebrae
Organisations of PANS
Output in cranial nerves and sacral spinal cord (end areas of stem)
no segmental ganglia
ganglia close to targets
long pre ganglionic and short post ganglionic nerves
Sympathetic NTs
Usually neuroepinephrine, sometimes ACh (used in sweat glands due to late developmental switch
Parasympathetic NTs
ACh
Sympathetic Neuromodulators
Enkephalin, ATP, Na, Neuropeptide Y, Vasoactive intestinal polypeptide, somatostatin
Parasympathetic Neuromodulators
ACh, Vasoactive Intenstinal Polypeptide, NO, ATP, Neuropeptide Y, Dynorphin, Somatostatin
Hyperhidrosis
Sweating a lot
sympathetic chain may be cut or injected with botulinum toxin to treat
Superior Cervical Ganglion
Sympathetic ganglion connected to head
Middle Cervical and stellate ganglia
Sympathatic ganglia connected to heart and lungs
Pre-vertebral ganglia
sympathetic ganglia connected to abdominal and pelvic organs
Parasympathetic Cranial Nerves
III Oculomotor
VII Facial
IX Glossopharyngeal
X Vagus
III Oculomotor
iris control
VII Facial
tear and salivary glands
IX Glossopharyngeal
parotid salivary gland
X Vagus
heart, lungs, and viscera
Iris Control
Superior cervical ganglion of sympathetic dilates
cillary ganglion of parasympathetic constricts
Sympathomimetic drugs
Amphetamines
Dilate pupils
Horner’s Syndrome
Tumour at apex of lung
leads to Ptosis, Miosis, Anhydrosis, and Hyperemia
Ptosis
droppy eyelids
Miosis
constricted pupils
anhydrosis
can’t sweat
Hyperemia
flushed skin
Lacrimation
Tears
controlled via VII facial nerve
Pterygopalatine ganglion
part of parasympathetic facial nerve VII
regulates secretions of the lacrimal gland and nasal mucosa
Submandibular
part of parasympathetic facial nerve VII
submandibular ganglion regulates secretions of submandibular and sublingual gland
Glossopharyngeal nerve IX
otic ganglion for parotid gland - controls salivary secretion
Heart rate
driven by CNS; when heart rate increases force of contraction and electrical conductance increase aswell
Bronchodilation
Bronchodilators are a type of medication that make breathing easier, relax lung muscles which are constricted by PANS
Danger response
PANS
Danger goes to spinal cord to greater sphanchnic nerve which is stimulates via adrenal medulla = adrenaline release
Chromaffin cells and SANS neurons
common developmental origin so they both are adrenal glands
Sympathomimetic actions during flight/fight
Pupils dilate via alpha1
Heart rate increases via beta1
Blood vessels contract by Peripheral vasoconstriction (alpha) and muscles vasodilation (beta2)
Kidney secrete renin via beta2
Lungs dilate via beta2
Glycogenolysis (beta2 and alpha)
Gluconeogenesis(beta 2 and alpha)
lipolysis beta 2 and 3 (maybe)
saliva secretion via alpha
gi tract decreases in motility beta2 and sphincters contract via alpha
Baroreflex
maintains blood pressure
Mictrurition reflex
pissing
Male genital reflexes
Erection is PANS and ejaculation is SANA
Defecation reflex
shitting
Peristalsis
Food in gut leads to serotonin release that stimulates the submucosal plexus that stimulates myenteric plexus = digestion
Megacolon
Defective nerve plexus due to hirschpring’s disease or congenital megacolon - looks very grpss