a brief overveiw of autonomic nervous system

8/6/2019 A Brief Overveiw of Autonomic Nervous System

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A BRIEF OVERVIEW OFA BRIEF OVERVIEW OFAUTONOMICAUTONOMIC

NERVOUS SYSTEMNERVOUS SYSTEM

DR SHARMISTHA BISWASDR SHARMISTHA BISWAS


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AUTONOMIC NERVOUS SYSTEMAUTONOMIC NERVOUS SYSTEM

MAINTAINS THE INTERNALMAINTAINS THE INTERNALENVIRONMENT ORENVIRONMENT OR MILIEU INTERIORMILIEU INTERIOR ORORHOMEOSTASISHOMEOSTASIS

DIVIDED INTO TWO MAJOR PARTS:DIVIDED INTO TWO MAJOR PARTS:

SYMPATHETICSYMPATHETIC

PARASYMPATHETICPARASYMPATHETIC

ALSO, ENTERIC NERVOUS SYSTEM ISALSO, ENTERIC NERVOUS SYSTEM ISANOTHER PARTANOTHER PART


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PREGANGLIONICPREGANGLIONIC

NEURONSNEURONS >>LATERALLATERALHORN CELLS OF ALLHORN CELLS OF ALL

THORACIC SEGMENTSTHORACIC SEGMENTS& UPPER 2& UPPER 2--3 LUMBAR3 LUMBAR

SEGMENTSSEGMENTS

THORACOTHORACO--LUMBARLUMBAR

OUTFLOWOUTFLOW


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PREGANGLIONIC NEURONS >PREGANGLIONIC NEURONS >

BRAIN STEMBRAIN STEM (3(3RDRD, 7, 7THTH, 9, 9THTH, 10, 10THTH CRANIALCRANIALNERVES)NERVES)

SACRALSACRAL (2(2NDND, 3, 3RDRD, 4, 4THTH )SEGMENTS OF)SEGMENTS OFSPINAL CORDSPINAL CORD

CRANIOCRANIO--SACRAL OUTFLOWSACRAL OUTFLOW


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POST GANGLIONIC NEURONS LOCATED INPOST GANGLIONIC NEURONS LOCATED IN

LATERAL GANGLIA :LATERAL GANGLIA : SYMPATHETIC TRUNKSYMPATHETIC TRUNK COLLATERAL :COLLATERAL : COELIAC, SUPR & INFERIORCOELIAC, SUPR & INFERIOR

MESENTERIC, AORTICOMESENTERIC, AORTICO--RENAL, SUPRRENAL, SUPR

HYPOGASTRICHYPOGASTRIC

TERMINAL :TERMINAL : IN SUPRAIN SUPRA--RENAL MEDULLA ASRENAL MEDULLA ASCHROMAFFIN CELLSCHROMAFFIN CELLS


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POST GANGLIONIC NEURONS LOCATED IN:POST GANGLIONIC NEURONS LOCATED IN:

CILIARY GANGLIA FOR 3CILIARY GANGLIA FOR 3RDRD CR NERVECR NERVE

(OCULOMOTOR)(OCULOMOTOR)

PTERYGOPALATINE & SUBMANDIBULAR GANGLIAPTERYGOPALATINE & SUBMANDIBULAR GANGLIAFOR 7FOR 7THTH CR NERVE (FACIAL)CR NERVE (FACIAL)

OTIC GANGLIA FOR 9OTIC GANGLIA FOR 9THTH CR NERVECR NERVE

(GLOSSOPHARYNGEAL)(GLOSSOPHARYNGEAL) FOR VAGUS & SACRAL COMPONENTS : IN WALLSFOR VAGUS & SACRAL COMPONENTS : IN WALLS

OF TARGET ORGANSOF TARGET ORGANS


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SENSORY COMPONENTS OFSENSORY COMPONENTS OF

SYMPATHETICSYMPATHETIC CONVEYCONVEY

VISCERAL PAINVISCERAL PAIN

THEIR CELLTHEIR CELL

BODIESBODIESSITUATED INSITUATED INDORSAL ROOTDORSAL ROOTGANGLIAGANGLIAOF ALLOF ALL

THORACIC &THORACIC &UPPER 2UPPER 2--33LUMBER SPINALLUMBER SPINALNERVESNERVES


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PARASYMPATHETIC CONVEYPARASYMPATHETIC CONVEY

GENERAL VISCERAL SENSATIONS LIKEGENERAL VISCERAL SENSATIONS LIKE

HUNGER, NAUSIAHUNGER, NAUSIA SENSATIONS FOR NORMAL VISCERALSENSATIONS FOR NORMAL VISCERAL

REFLEXES, eg. CAROTID SINUS, HERINGREFLEXES, eg. CAROTID SINUS, HERINGBREUERS REFLEX, REFLEX ACT OFBREUERS REFLEX, REFLEX ACT OF

MICTURITIONMICTURITIONVISCERAL PAIN SENSATION FROM SOMEVISCERAL PAIN SENSATION FROM SOME

PELVIC VISCERAPELVIC VISCERA


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PARASYMPATHETIC:PARASYMPATHETIC:CELL BODIES OF THESE NEURONESCELL BODIES OF THESE NEURONES

LOCATED INLOCATED IN

SUPERIOR & INFERIOR GANGLIA OFSUPERIOR & INFERIOR GANGLIA OFGLOSSOPHARYNGEAL NERVEGLOSSOPHARYNGEAL NERVE

INFERIOR(NODOSE) GANGLION OFINFERIOR(NODOSE) GANGLION OFVAGUS NERVEVAGUS NERVE

DORSAL ROOT GANGLIA OF SDORSAL ROOT GANGLIA OF S22, S, S33, S, S44


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ANATOMY OF SYMPATHETICANATOMY OF SYMPATHETIC

NERVOUS SYSTEMNERVOUS SYSTEM PRESENTS A DEFINITE ANATOMICALPRESENTS A DEFINITE ANATOMICAL

ENTITYENTITY

CONSISTS OF :CONSISTS OF :

A PAIR OF GANGLIONATED SYMPATHETIC TRUNK /A PAIR OF GANGLIONATED SYMPATHETIC TRUNK /

CHAINCHAIN

THEIR RAMI OF COMMUNICATIONS, BRANCHES,THEIR RAMI OF COMMUNICATIONS, BRANCHES,PLEXUSES & SUBSIDIARY GANGLIAPLEXUSES & SUBSIDIARY GANGLIA


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SYMPATHETIC TRUNKSYMPATHETIC TRUNK FROM BASE OF SKULL > 1FROM BASE OF SKULL > 1STST COCCYGEALCOCCYGEAL

VERTEBRA > GANGLIONIC IMPARVERTEBRA > GANGLIONIC IMPAR

3 GANGLIA IN CERVICAL REGION3 GANGLIA IN CERVICAL REGION

SUPERIOR : UPPER 4 CERVICAL FUSE TO FORMSUPERIOR : UPPER 4 CERVICAL FUSE TO FORM

MIDDLE : 5MIDDLE : 5TH &TH & 66THTH

INFERIOR : 7INFERIOR : 7TH &TH & 88THTH

11 GANGLIA IN THORACIC REGION11 GANGLIA IN THORACIC REGION

4 LUMBAR4 LUMBAR

4 SACRAL4 SACRAL

STELLATEGANGLIONSTELLATEGANGLION


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..Thoracic & upper 2Thoracic & upper 2--33lumbar sympatheticlumbar sympatheticganglia connected toganglia connected tocorresponding spinalcorresponding spinalnerves bynerves by

Grey ramiGrey rami

communicantescommunicantes

White ramiWhite ramicommunicantescommunicantes

Rest of sympatheticRest of sympatheticganglia connected toganglia connected tocorresponding spinalcorresponding spinalnerves only by greynerves only by greyramirami


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.. White ramiWhite rami : convey: convey

preganglionic neuronspreganglionic neuronsfromfromlateral horn cells of alllateral horn cells of all

thoracic segmentsthoracic segments & upper& upper22--3 lumbar segments3 lumbar segments..

Sensory sympathetic fibresSensory sympathetic fibresfrom viscera whose cells offrom viscera whose cells of

origin lie in dorsal rootorigin lie in dorsal rootgangliaganglia

GREY RAMIGREY RAMI: CONVEY: CONVEYPOSTPOST--GANGLIONIC FIBERSGANGLIONIC FIBERS FROMFROMLATERAL GANGLIALATERAL GANGLIA

THROUGH ALL 31 PAIRS OFTHROUGH ALL 31 PAIRS OFSPINAL NERVES >supplySPINAL NERVES >supplyskin of body wall andskin of body wall andlimbs,vasodilator fibres tolimbs,vasodilator fibres toskeletal musclesskeletal muscles


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MOTOR FIBRES OF SYMPATHETICMOTOR FIBRES OF SYMPATHETIC

SYSTEMSYSTEM PreganglionicPreganglionic fibers: thinlyfibers: thinly

myelinatedmyelinated

Arise from lateral horn cells of TArise from lateral horn cells of T11LL2,32,3 > ventral root >trunk> white> ventral root >trunk> white

ramirami > lateral ganglion of spinal> lateral ganglion of spinalcordcord

After reaching ganglia, terminateAfter reaching ganglia, terminateinto 3 waysinto 3 ways::

1.1. Relay to cells of same ganglionRelay to cells of same ganglion

2.2. Ascend / descend along sym trunk toAscend / descend along sym trunk torelay in ganglion above / belowrelay in ganglion above / below

3.3. May pass unMay pass un--interrupted through syminterrupted through sym trtrto form thoracicto form thoracic splanchnicsplanchnic (greater,(greater,lesser, least) or lumberlesser, least) or lumber splanchnicsplanchnicnerve. They synapse in the collateral /nerve. They synapse in the collateral /

terminal ganglia.terminal ganglia.


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Clinical anatomy of Sympathetic N SClinical anatomy of Sympathetic N S

HornersyndromeHornersyndrome:: lesion oflesion of infinf cervical ganglion:cervical ganglion:1.1. Constriction of pupilConstriction of pupil

2.2. Drooping of upper eyeDrooping of upper eye--lidlid

3.3. EnophthalmosEnophthalmos

4.4. Absence of sweatingAbsence of sweating

RaynaudsRaynauds diseasedisease :: sympathetic trunk section belowsympathetic trunk section belowTT33 relievesrelieves vasovaso--spasm of upper limbsspasm of upper limbs

Vasospasm of lower limbsVasospasm of lower limbs relieved by sympatheticrelieved by sympathetictrunk section including 3 lumber gangliatrunk section including 3 lumber ganglia

SupraSupra--renal glandrenal glandpreganglionicpreganglionic TT88--LL11 > synapse with> synapse with chromaffinchromaffincells> act as postcells> act as post--ganglionicganglionic neuronsneurons


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MOTOR FIBRES OF SYMPATHETICMOTOR FIBRES OF SYMPATHETICSYSTEMSYSTEM

Postganglionic fibers: nonPostganglionic fibers: non--myelinatedmyelinated

Arranged in 2 groups :Arranged in 2 groups :

Those arising fromThose arising from laterallateralgangliaganglia > function: to> function: toregulate body temperature,regulate body temperature,blood pressureblood pressure

Those arising fromThose arising from collateralcollateralgangliaganglia > function: to supply> function: to supplydeep lying organs throughdeep lying organs throughperiperi--arterial plexusesarterial plexuses..


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Preganglionic neurons :Preganglionic neurons : shortshort Postganglionic neurons:Postganglionic neurons: longlong

One preganglionic neuron synapse with 20 or moreOne preganglionic neuron synapse with 20 or morepostganglionic neuronspostganglionic neurons

Sympathetic is nerve of emergency (Nerve of today)Sympathetic is nerve of emergency (Nerve of today) :: Cuteneous blood vessels: constrictCuteneous blood vessels: constrict

Coronary & skeletal vessels : dilateCoronary & skeletal vessels : dilate

Heart rate: accelerated, blood pressure raisedHeart rate: accelerated, blood pressure raised

Pupil : dilatePupil : dilate

Bronchioles: dilateBronchioles: dilate

Intestinal peristalsis: suppressed, sphincters : closed.Intestinal peristalsis: suppressed, sphincters : closed.

Not essential to life, subject can live if no physical /Not essential to life, subject can live if no physical /metabolic stress is there.metabolic stress is there.


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PARASYMPATHETIC SYSTEM:PARASYMPATHETIC SYSTEM:

NO DEFINITE ANATOMICAL ENTITYNO DEFINITE ANATOMICAL ENTITY

33rdrd crcr nervenerve((OculomotorOculomotor) :) :

PrePre--ganglionicganglionicneurons located inneurons located inEdingerEdinger--WestphalWestphalnucleus >nucleus > relay inrelay inciliaryciliary ganglia > shortganglia > shortciliaryciliary nerves> supplynerves> supplysphinctersphincter pupillaepupillae &&ciliarisciliaris musclemuscle


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77thth crcr nerve (Facial):nerve (Facial):

PrePre--ganglionicganglionic neuronsneuronslocated inlocated in suprsuprsalivatorysalivatory nucleus >nucleus >relay inrelay in pterygopalatinepterygopalatine&& submandibularsubmandibular gangliaganglia>> secretomotorsecretomotor fibresfibres totolacrimallacrimal, nasal, palatine, nasal, palatine&& submandibularsubmandibular glandsglands


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99thth crcr nervenerve

((GlossopharyngealGlossopharyngeal) :) : PrePre-- ganglionicganglionic neuronsneurons

located inlocated in infrinfr

salivatorysalivatory nucleus >nucleus >relay inrelay in oticotic ganglia >ganglia >throughthroughAuriculotemporalAuriculotemporal nvnv >>

secretomotorsecretomotor && vasovaso--dilatordilator fibresfibres to parotidto parotid

glandgland

..


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SYSTEMSYSTEM

Vagus :Vagus : pre ganglionicpre ganglionicneurons located in dorsalneurons located in dorsalnucleus of vagus>relay innucleus of vagus>relay interminal ganglia close toterminal ganglia close totarget organs to heart,target organs to heart,

lungs, stomach, gutlungs, stomach, gut

Sacral components :Sacral components : prepreganglionic neurons locatedganglionic neurons locatedin lateral horn cells of Sin lateral horn cells of S22 ,,SS

33

,S,S44

>pelvic sp. Nv & inf>pelvic sp. Nv & infhypogastric plexus > relayhypogastric plexus > relayin walls of target organs :in walls of target organs :urinary bladder, testis,urinary bladder, testis,ovary, penis, uterus,ovary, penis, uterus,rectumrectum

a brief overveiw of autonomic nervous system

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