Autonomic Nervous System (ANS)

Assoc. Prof. Wantanee Trakulrungsi Department of Anatomy, Fa

culty of Science, Mahidol University.

Autonomic Nervous System (ANS) Sympathetic Nervous

System (Thoracolumbar division Or Adrenergic division)

Parasympathetic Nervous System (Craniosacral division Or Cholinergic division)

Comparision of the somatic and autonomic nervous system.

Sympathetic pathways

(a) Synapse in a sympathetic chain ganglion at the same level.(b) Synapse in a sympathetic chain ganglion at a different level. (c)Synapse in a collateral ganglion anterior to the vertebral column.

Terms - Preganglionicsympat het i c neur ons: I n i

ntermediolateral cell column of -T1 L2 spi nal cor d segment s

- Preganglionic sympathetic fiber s - Postganglionicsympat het i c neur ons: I n t he

sympathetic ganglion. - Postganglionic sympathetic fi

bers. - White ramus communicans. - Gray ramus communicans. - Splanchnic nerves

Sympathetic ganglion

1. Paravertebral ganglion : Locate beside the vertebral column (In sympathetic chain)

Superior Cervical Ganglion (SCG)

- Cervical ganglion 3 pair Middle Cervical Ganglion (MCG)

Inferior Cervical Ganglion (ICG)

- Thoracic ganglion 12 pair

- Lumbar ganglion 4 (5) pair

- Sacral ganglion 4 (5) pair

- Coccygeal ganglion 1 ganglion (single) called ganglion impar

Stellate ganglion (ICG + T1 ganglion)

Sympathetic ganglion

2. Prevertebral ganglion

- Celiac ganglion

- Superior mesenteric ganglion

- Inferior mesenteric ganglion

- Superior hypogastric ganglion

- Inferior hypogastric ganglion

Sympathetic ganglionParavertebr

al ganglionPrevertebra l ganglion

Postganglionic sympathetic fibers

1. Travel along the spinal nerves.

2. Travel along the blood vessel, e.g. internal carotid artery.

3. Travel straight to the target organ.e.g. fibers to the heart.

Perivascular plexus- Sympathetic : postganglionic sympathetic fibers-Parasympathetic : preganglionic parasympathetic fibers- Sensory fibers

Pain

- visceral pain or real pain

- Referred pain

Splanchnic nerve (= preganglionic sympathetic fibers)

- Thoracic splanchnic nerve

- Lumbar splanchnic nerve

- Sacral splanchnic nerve

Thoracic splanchnic nerve 1. Greater sp.n. : Preganglionic sympathetic fibers that pass through the T5- T9 ganglia without synapse

synapse at celiac ganglion

2. Lesser sp.n. : pass through T10,T11 ganglion without synapse

synapse at Aorticorenal ganglion

3. Lowest sp.n.: pass through T12ganglion without synapse

synapse at renal plexus

Lumbar splanchnic nerveL1 ganglion intermesenteric ganglion

L2 ganglion

L3 ganglion

superior hypogastric

L4 gangion ganglion at the bifurcation of

Aorta

Sacral splanchnic nerve S1 ganglion

S2 ganglion

synapse at Inferior

hypogastric ganglion in

S3 ganglion pelvic cavity

S4 ganglion

Lumbar and Sacr al Spl an chni c ner ves

Parasympathetic NervousSystem

(Craniosacral Outflow or C holinergic Outflow) Cranial par

t : From para sympathetic

nucleus of C N III, VII, IX,

X Spinal part

: From the intermediola

teral gray co lumn of -S2

S4

Parasympathetic nervous system of the Head and Neck

Nucleus Preganglionic

fibers travel

along which

cranial nerve?

Preganglionic

fibers accompany

which nerve?

Synapse at

which

ganglion?

Postganglionic

fibers hitch a ride

with which nerve?

Target organs What happens to that organ?

Edinger-Westphal

nucleus in

midbrain

CN.III - oculomotor nerve

to inferior oblique

m.

- Ciliary

ganglion

- short ciliary nerve- Pupillary constrictor of iris

and ciliary muscle of ciliary

body

-pupil constrict

- contraction of ciliary m. -->

increase bulging of lens for

close vision

Superior

salivatory nucleus

relate to

medullopontine

junction

CN.VII

(Nervous

intermediate)

- greater superficial

petrosal nerve

vidian nerve

- chorda tympani

nerve

-pterygopal

atine

ganglion

- subman

dibular

ganglion

-maxillary n.

- lingual n.

- Lacrimal gland

- Oral, palaline glands and

Nasal glands

- submandibular and

sublingual salivary glands

-secretion of tear

- secretion of mucous glands in

that area

- secretion of salva from sub

mandibular and sublingual

salivary glands

Inferior salivatory

nucleus in

medulla

CN.IX - tympanic nerve

lesser superficial

petrosal nerve

-Otic

ganglion

-auriculotemporal

n.

-parotid salivary gland -secretion of saliva from parotid

gland

Parasympathetic of CNIII *Pr egangl i oni c par asy

mpathetic neurons locate at t he - Edinger Westphal

nucleus. * Preganglionic parasy

mpathetic fibers pass alon g CNIII CNIII to the infe

rior oblique muscle * Synapse at Ciliary ganglion. * Postganglionic paras

ympat het i c fi ber s go t o 1 . Pupillary constrictor muscles of iris and 2. Ciliary muscles of c

i l i ar y body

Parasympathetic of CNVII I * Preganglionic parasym

pathetic neurons locate at t he Superior salivato ry nucleus

* Preganglionic parasy mpat het i c fi ber s pass al

ong t ympani CNVII (Nerv ous intermediate)

Chorda tympani nerve * Synapse at Subman

dibular ganglion. * Postganglionic paras

ympat het i c fi ber s go t o 1.Submandibular sali

vary gland and 2. Sublingual salivarygl and

Parasympathetic of CNVII II. * Preganglionic parasympatheti

c neurons locate at t he Superior salivatory nucleu

s * Preganglionic parasympathetic f

ibers pass along CNVII (Nervous int ermediate)

Greater superficial petrosal ner ve

Nerve of pterygoid canal (Vidiannerve) * Synapse at Pterygopalatineganglion. * Postganglionic parasympatheti

c fibers go to 1. Lacrimal gland and 2 . Mucous glands of Nose, pala

te and pharynx

- Superior salivatory nnnnnnn-Submandibular gangl i on-Pterygopalatine gangl i on

Parasympathetic of CNIX *Preganglionic parasympathetic

neur ons l ocat e at t he Inferior salivatory nucl

eus * Preganglionic parasympath

etic fibers pass along CNIX

t ympani c ner ve t ympani c plexus lesser superficial petros

al ner ve * Synapse at Otic ganglion. * Postganglionic parasympat

hetic fibers go to Parotid salivary gland

- Inferior salivatory nnnnnnn- Otic ganglion- Parotid salivarygl and

Parasympathetic of CNX - Dorsal motor nucleus

of vagus nerve - Preganglionic parasymp

athetic fibers travel along t he vagus nerve.

- Postganglionic parasym pathetic neurons locate

near or within the wall of th e eff ect or or gans

e.g. Myenteric ganglia o f GI tract

- Postganglionic parasym pathetic fibers end at the s

mooth muscle of the GI tra ct

1. What is the name of the nucleus? 2. Preganglionic parasympathetic fibers travel along

which cranial nerve? 3. What is the name of the parasympathetic ganglion?

Where is it located? nnnnnnn nnnnnnnn nnnnnn nnnnn n nnnn4 .

with which branch of which nerve? 5 . ?What is the effector organ 6 . ?What happens to that organ

Effects of the Sympathetic and Parasympathetic Divisions of the Autonomic Nervous system

Autonomic innervation 1. opposite effect = dual, antagonistic autonomic innervation e.g. Heart

sti.parasym (from vagus nerve)car cardiac deceleration or bradycardia

* slowing of the beat * reduction in the force of contraction * reduction in the ventricular output (blood volume per beat)

sti.symp . (cardiac nerve from the cervical ganglia) cardiac acceleration or tachycardia

* in contractile force * in volume of blood pumped per beat

2 . Dual but different effect e.g. salivary gland sti. Symp. produces a thick mucus secretion sti. Parasymp. Produces copious of a clear, watery,seroussecretion

3 Receive innervation from only one of the division e.g. sweat gland and erector pili muscles symp. nnnnnnnnnnnn nn nnnnnnnnn nnnnnn nn nnnnnn.

References 1) Marieb,E.N.: Essentials of Human Anatomy

& Physiology, Sixth Edition, Addison Wesley Longman, Inc.,2000.

2) Moore, K.L. and Anne M.R. Agur. Essential Clinical Anatomy, Second Edition, Lippincott Williams & Wilkins, 2 0 0 2 .

3 18) Burt, A.M. Textbook of Neuroanatomy, chapter . W.B. Saunders Company, 1 9 9 3 .