Somatic efferent innervation

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ACh Acetylcholine NE Norepinephrine
Somatic efferent innervation
ACh
Visceral efferent innervation
ACh or NE
ACh
Autonomic ganglion
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Autonomic Nervous System

• basic anatomy of ANS
• ANS vs PNS
• divisions of ANS
• sympathetic division
• anatomy function
• ANS plexuses
• sympathetic response
• adrenal gland
• parasympathetic division
• anatomy function
• visceral reflexes
• stress the ANS
• referred pain anatomy

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CNS
PNS
Sensory Somatic visceral
Motor
Visceral
Somatic
Parasympathetic
Sympathetic
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Autonomic Nervous System

• Visceral sensory motor system
• Innervates viscera, smooth muscle and glands
• Autonomic self governed
• Adjusts visceral functions to the bodys needs
• Responsible for visceral reflexes

CN IX
High BP
CN X
Decrease Heart rate
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Basic anatomy of ANS

• Preganglionic neuron
• cell body in brain or spinal cord (lateral horn)
• axon is myelinated
• Synapses in ganglion

• Postganglionic neuron
• cell body in autonomic ganglion
• axon is unmyelinated
• synapses on visceral effector

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• Sympathetic
• Speeds up
• Fight or flight
• Parasympathetic
• slows down
• rest digest

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• Sympathetic division (thoracolumbar)
• preganglionic neuron cell body in T1-L2 of spinal
  cord
• Ganglia near spine
• connected by a chain
• (sympathetic chain)
• Short preganglionic neuron
• Long postganglionic neuron
• Parasympathetic division (craniosacral)
• preganglionic neuron cell body in S2-S4 of spinal
  cord brainstem
• CNs III, VII, IX X
• Ganglia in organ wall
• Ganglia are not connected
• Long preganglionic neuron
• Short postganglionic neuron

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Anatomy of sympathetic chain
Posterior (dorsal)
Dorsal ramus
Communicating rami
Ventral ramus
Sympathetic ganglion
Anterior (ventral)
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Sympathetic chain in thorax
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Sympathetic innervation of the heart
brain
Lateral horn
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Sympathetic pathways

• all this innervation is
• BILATERAL (right left)
• sympathetic pathways
• innervate sweat gland, arrector
• pili smooth muscle of blood
• vessels peripherally
• organ responses?
• sympathetic pathways
• carry noxious sensory
• information (except in pelvis)

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Adrenal gland
Adrenal cortex
Adrenal medulla

• Cortex steroid hormones (endocrine system)
• Medulla modified sympathetic ganglion
• secretes epinephrine (adrenaline)
  norepinephrine
• innervated by preganglionic sympathetic neurons
• products get secreted into bloodstream

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Parasympathetic pathways
Cranial nerves III, VII, IX X Sacral nerves
S2-S4 NT acetylcholine Also bilateral
innervation Carries most sensory info
except noxious stimuli
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Plexuses of ANS sympathetic parasympathetic

• Cardiac plexus
• Pulmonary plexus
• Celiac (solar) plexus
• Superior mesenteric
• Inferior mesenteric
• Hypogastric

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(No Transcript)
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Visceral reflex
CN IX
CN IX
Low BP
High BP
sympathetic
CN X Vagus
Increase HR And constrict BV
Decrease HR And dilate BV
Beta adrenergic blockers Block sympathetic
response
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vagus
vagus

• Asthma
• parasympathetic response
• bronchospasm
• increased gland activity
• treat with B2 adrenergic agonists
• (stimulate sympathetic response)

Phenylephrine vs pseudoephedrine
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T1-T4 receive visceral afferents from heart
T1 dermatome
Sensory from skin green Sensory from heart red
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Referred Pain

• Organ skin pain fibers travel to the spinal
  cord together
• Organ pain misinterpreted as skin pain (referred
  pain)
• Heart skin in left arm spinal nerves T1-T5
• Heart attack (pain) is felt in skin (pain) along
  left arm chest

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What is STRESS?

• Short term amp to long term amp
• Year after year

Problems! - hypertension - ulcers -
constipation - bladder infections -
Raynauds - sexual dysfunction