Lection:
Peripheral nervous system
ANATOM.UA
PART 1
Ch. 1 Anatomia generalis
PART 2 – SYSTEMATA MUSCULOSKELETALIA
Ch. 2 Ossa
Ch. 3 Juncturae
Ch. 4 Musculi
PART 3 – SYSTEMATA VISCERALIA
Ch. 5 Systema digestorium
Ch. 6 Systema respiratorium
Ch. 7 Cavitas thoracis
Ch. 8 Systema urinarium
Ch. 9 Systemata genitalia
Ch. 10 Cavitas abdominopelvica
PART 4 – SYSTEMATA INTEGRANTIA I
Ch. 11 Glandulae endocrinae
Ch. 12 Systema cardiovasculare
Ch. 13 Organa lymphoidea
PART 5 – SYSTEMATA INTEGRANTIA II
Ch. 14 Systema nervosum
Ch. 15 Organa sensuum
Ch. 16 Integumentum commune
ANATOM.UA
https://fipat.library.dal.ca/ta2/
ANATOM.UA
The Spinal Cord
Foramen magnum to L1 or L2
Runs through the vertebral canal of the vertebral column
Functions
1. Sensory and motor innervation of entire body inferior to the head through the spinal nerves
2. Two-way conduction pathway between the body and the brain
3. Major center for reflexes
Fetal 3rd month: ends at coccyx
Birth: ends at L3
Adult position at approx L1-2 during childhood
End: conus medullaris
This tapers into filum terminaleof connective tissue, tethered to coccyx
Spinal cord segments are superior to where their corresponding spinal nerves emerge through intervetebral foramina (see also fig 17.5, p 288)
Denticulate ligaments: lateral shelves of pia mater anchoring to dura (meninges: more later)
Spinal cord
http://www.apparelyzed.com/spinalcord.html
Spinal nerves
Part of the peripheral nervous system
31 pairs attach through dorsal and ventral nerve roots
Lie in intervertebral foramina
Spinal nerves continued
Divided based on vertebral locations
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
Cauda equina (“horse’s tail”): collection of nerve
roots at inferior end of vertebral canal
Spinal nerves continued
Note: cervical spinal nerves exit from
above the respective vertebra
Spinal nerve root 1 from above C1
Spinal nerve root 2 from between C1 and C2,
etc.
Clinically, for example when referring to
disc impingement, both levels of vertebra
mentioned, e.g. C6-7 disc impinging on
root 7
Symptoms usually indicate which levelMore about spinal nerves in the peripheral nervous system lecture
Protection:BoneMeningesCSF (cerebrospinal fluid)3 meninges:
dura mater (outer)arachnoid mater (middle)pia mater (inner)
3 potential spacesepidural: outside durasubdural: between dura &
arachnoidsubarachnoid: deep to arachnoid
Spinal cord coverings and spaces
LP (lumbar puncure) = spinal tap
(needle introduced into subdural space to collect CSF)
Lumbar spine needs
to be flexed so can go
between spinous
processes
Epidural space is external to duraAnesthestics are often injected into epidural spaceInjection into correct space is vital; mistakes can be lethal
Originally thought to be a narrowfluid-filled interval between the duraland arachnoid; now known to be an artificial space created by the separation of the arachnoid from the dura as the result of trauma or some ongoing pathologic process; in the healthy state, the arachnoid is attached to the dura and a naturally occurring subdural space is not present. http://cancerweb.ncl.ac.uk/cgi-bin/omd?subdural+space
Spinal cord anatomy Posterior median sulcus (“p”)
Anterior median fissure (“a”)
White matter (yellow here)
Gray matter (brown here)“p”
“a”
Gray/White in spinal cord Hollow central cavity (“central
canal”)
Gray matter surrounds cavity
White matter surrounds gray matter (white: ascending and descending tracts of axons)
“H” shaped on cross section
Dorsal half of “H”: cell bodies of interneurons
Ventral half of “H”: cell bodies ofmotor neurons
No cortex (as in brain)
Dorsal (posterior)
white
gray
Ventral (anterior)
Central canal______
Spinal cord anatomy Gray commissure with central canal
Columns of gray running the length of the spinal cord
Posterior (dorsal) horns (cell bodies of interneurons)
Anterior (ventral) horns (cell bodies of motor neurons)
Lateral horns in thoracic and superior lumbar cord
**
*
*
White matter of the spinal cord(myelinated and unmyelinated axons) Ascending fibers: sensory information from sensory
neurons of body up to brain
Descending fibers: motor instructions from brain to spinal cord
Stimulates contraction of body’s muscles
Stimumulates secretion from body’s glands
Commissural fibers: white-matter fibers crossing from one side of cord to the other
Most pathways cross (or decussate) at some point
Most synapse two or three times along the way, e.g. in brain stem, thalamus or other
The Brain: embryonic
development Develops from neural tube
Brain subdivides into
Forebrain
Midbrain
Hindbrain
These further divide, each with a fluid filled region: ventricle, aqueduct or canal
Spinal cord also has a canal
Two major bends, or flexures, occur (midbrain and cervical)
Brain development Learn forebrain, midbrain and hindbrain in (b)
See next color coded pics in reference to (d)
Learn (e)
Encephalos means brain (otherwise you don’t need to learn “c”)
Space restrictions force cerebral hemispheres to grow posteriorly over rest of brain, enveloping it
Cerebral hemispheres grow into horseshoe shape (b and c)
Continued growth causes creases, folds and wrinkles
Anatomical classification Cerebral hemispheres
Diencephalon
Thalamus
Hypothalamus
Brain stem
Midbrain
Pons
Medulla
Cerebellum
Spinal cord
Parts of Brain
Cerebrum
Diencephalon
Brainstem
Cerebellum
Nervous System
Marieb 11.1
Martini 12-4
Comparison of Structural Classes of Neurons
Marieb T11.1.1
Saltatory Conduction
Marieb 11.16
Synaptic Cleft: Information Transfer
Marieb 11.18
Freeman 45-17a
• Brain
WHAT PARTS DO YOU KNOW THAT
ARE IN THE NERVOUS SYSTEM?
• Spinal Cord
• Peripheral Nerves
What makes up the brain, the spinal cord or
your peripheral nerves?
• Neurons are “the cell”
• Cell body
• Nucleus
• Axon
• Dendrite
• What do you think surrounds the cell?
• What other organelles would be needed?
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
How are neurons connected?
• Synapses!!
Why are neurons connected?
More neuron connections!
How does the Synapse carry the signal?
1. Electrical current travels down the axon
2. Vesicles with chemicals move toward the membrane - what is
that called?
3. Chemicals are released and diffuse toward the next cell’s
plasma membrane
4. The chemicals open up the transport proteins and allow the
signal to pass to the next cell - what type of diffusion is this?
There are lots of proteins and chemicals in your
body to do the work
Why is it important that it is an electrical current?
Are all neurons equal in size?• Brain vs spinal cord vs peripheral nerves?
About how many neurons are in the human brain? 100 billion
1 billion
around 15 feet
About how many neurons are in the spinal cord?
How long do you think the longest axon in the world is?
How many synapses
are in one neuron? 1,000 to 10,000!!
• Looking at the actual cells - how do they work?
• Looking at the connections - how and when do they work?
• Looking at what can change normal cells and connections
• Looking at diseases that occur in the brain
• One of the largest areas still unknown
• The you that is you is because of your neurons connecting!
What do you think can change
neurons and their connections?
• Accidents
• Drugs
• Alcohol
• Disease
Space Restriction and Brain Development
Marieb 12.3
Marieb 12.6ab
Ventricles of the Brain
Marieb 12.5
Functional Areas of the Cerebral Cortex
Marieb 12.8a
Functional Areas of the Cerebral Cortex
Marieb 12.8b
Primary Motor Cortex
Marieb 12.9.1
Sensory Areas
Marieb 12.8a
Association Areas
Marieb 12.8a
Tortora 14.12
Marieb 12.10ab
Diencephalon
Marieb 12.12
Meninges
Marieb 12.24a
1. Lateral ventricle
2. Interventricular foramen
3. Third ventricle
4. Cerebral aqueduct
5. Fourth ventricle
6a. Median aperture 6b. Lateral aperture 6c. Central canal (spinal cord)
7. Subarachnoid space
8. Arachnoid villi
9. Dural sinuses
Marieb 12.26b
Spinal Cord
Marieb 12.29a
Cross-Sectional Anatomy of the Spinal Cord
Anterior median fissure – separates anterior funiculi
Posterior median sulcus – divides posterior funiculi
Marieb 12.31a
Gray Matter and Spinal Roots
Marieb 12.31b
Gray Matter: Organization
Marieb 12.32
Structure of a Nerve
Marieb 13.3b
Cranial Nerves
Marieb 13.5a
Spinal Nerves
Marieb 13.6
Spinal Nerves: Roots
Marieb 13.7a
Marieb 13.7b
Martini 13-11
Freeman 45-20
Martini 16-10
Comparison of Somatic and Autonomic Systems
Marieb 14.2
The nervous system for topographicindication is divided into two divisions: thecentral nervous system (CNS) i peripheralnervous system (PNS).
Brain and spinal cord are related to the central nervous system (CNS).
Nerves, ganglia, nerve plexus and nerve endings are the peripheral nervous system (PNS).
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Overview of the autonomic (vegetative) nervous system
Overview of the autonomic (vegetative) nervous system
For anatomical and functional
principle nervous system is divided
into two parts: the somatic nervous
system and autonomic nervous
system (ANS). The division of
somatic nervous system and
autonomic was proposed in the late
XVIII century by K.Bisha.
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Overview of the autonomic (vegetative) nervous system
The somatic nervous system innervates the
soma (skin), skeletal muscles, joints. The
somatic nervous system of the body
provides a link with the environment.
The autonomic nervous system innervates
internal organs and coordinates their work.
Provides adaptive-trophic effects on the
whole body.
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Overview of the autonomic (vegetative) nervous system
In the current international anatomical
nomenclature (Sao Paulo, 1997) instead of
the term VPS or autonomic nervous
system is proposed term "autonomous part
of the peripheral nervous system," but in
the national educational and scientific
literature on anatomy, physiology and also
in the clinic is common to use the term
"VNS ".
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Overview of the autonomic (vegetative) nervous system
VNS is a part of the nervous system,
that conducts the functions of the
homeostasis regulation and getting
used to the environmental conditions
that Are constantly changing. VNS
innervates the visceral organs and
conducts the adapto- trophical
influence on the whole organism.
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Overview of the autonomic (vegetative) nervous system
VNS for anatomical and functional
principle is divided into two parts: the
sympathetic part of ANS or sympathetic
nervous system and parasympathetic ANS
part or parasympathetic nervous system.
The term "parasympathetic nervous
system" was introduced in 1925 D.Lenhli.
In recent years, within the SPA is isolated
metasympatic nervous system (research
A.D.Nozdrachov, 1983)
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Autonomic features or functions ofplant life (breathing, digestion, dis-multiplication, selection, etc.) areregulated by structure-roundsautonomic nervous system.
Overview of the autonomic (vegetative) nervous system
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Dzh.Lenhli in 1889 divided theentire autonomic nervous systeminto two main divisions -parasympathetic andsympathetic. Separately, it hasbeen allocated so-called enteralsystem or intestinal plexus.
Overview of the autonomic (vegetative) nervous system
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International anatomical nomenclature (SaoPaulo, 1997) offers not use the termautonomous (vegetative) nervous system toavoid many significance. Instead it wasproposed the term ‘autonomousdepartment’; autonomous part of theperipheral nervous system, divisioautonomica; pars autonomica systematisnervosi peripherici, which distinguishes thesympathic part, pars sympathica, and theparasympathetic part, pars parasympathica.
Overview of the autonomic (vegetative) nervous system
Overview of the autonomic (vegetative) nervous system
Overview of the autonomic (vegetative) nervous system
Overview of the autonomic (vegetative) nervous system
85
However, it should be noted, that inthe national scientific and educationalliterature, the term "autonomic nervoussystem" is more prevalent and thereforemore understandable. In addition, inrecent years due to research-A.D.Nozdracheva Jenny (1983, 1989)within the autonomic nervous system,probes offer quality local highlightanother part (system unit) -metasymphatic.
Overview of the autonomic (vegetative) nervous system
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According to the modern definitionof autonomous (vegetative) nervoussystem - a part of the nervous systemthat serves as the regulating constancyof internal environment (homeostasis)and in-application of the terms of theNavier-former environment that isconstantly changing.
Overview of the autonomic (vegetative) nervous system
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Regulation of homeostasis
includes the support for the body at
the right level of biochemical,
physical, chemical, and other
enzymatic constants, violation of
which is shown not only by
numerous vegetative, but also by
somatic dysfunction.
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Regulation of homeokinesis includesproviding of various forms (mental,emotional, physical) and implementation ofbiological motivation of the whole organism.Violation of adequate homeokinetic reactionschanges behavior, contributesmaladjustment and eventually causes theemerge of mental illness or death of theorganism.
Overview of the autonomic (vegetative) nervous system
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Nowadays the sympatheticautonomic (vegetative) nervoussystem is seen as a system alarm,mobilizing defenses and resourcesfor active interaction withenvironmental factors, i.e. asergotropic system.
Overview of the autonomic (vegetative) nervous system
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Parasympathetic part, as well asmetasympathetic, was designed torestore and maintain homeostasis,disturbed as a result of the activity ofthe body, that carries trophotropicimpact. This metasympatheticautonomous (vegetative) nervoussystem implements this featureregionally (a separate organ or part).
Overview of the autonomic (vegetative) nervous system
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The central segmental structures includeautonomic parasympathetic nucleus III, VII,IX, X pairs of cranial nerves, sacralparasympathetic neurons of the spinal cordand sympathetic neurons located in thelateral horns of the spinal cord in thethoraco-lumbar region. These centralsegmental centers (centers) are genuineautonomous centers because of theirfeatures and patterns of operation.
Overview of the autonomic (vegetative) nervous system
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The most significant differences betweenthe morphological autonomous (vegetative)nervous system and the somatic nervoussystem are:
1) placing cells of the sympathetic andparasympathetic parts in certain places CNS(segmental centers);
2) the location of the second neuron axon andneuron bodies third simple reflex arcoutside the CNS.
Overview of the autonomic (vegetative) nervous system
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Bodies of the third neuronsaccumulate as vegetative ganglions.That’s why the fibers of the autonomic(vegetative) nervous system, thatcarry impulses from the spinal cord orthe brain, are called preganglionarand the fibers that carry impulsesfrom the ganglion to the organ –postganglionar.
Overview of the autonomic (vegetative) nervous system
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For the degree of distance from the centralnervous system and for topography vegetativenodes are divided into:
1) placed on either side of the spine nodes andqueues or paravertebral nodes (nodes sympathetictrunk);
2) placed in front spine units or second stageprevertebral units;
3) located nearby organs or tissues of the internalcomponents of phase III (respectively, extra- andintra-organ). Units I and II stage is sympathetic;Third stage units are predominantlyparasympathetic.
Overview of the autonomic (vegetative) nervous system
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At the end of all preganglionic sympatheticand parasympathetic neurons, and interminals of the most postganglionicparasympathetic fibers releasedneurotransmitter acetylcholine. In addition,some postganglionic sympathetic fibers, thatinnervate sweat glands, are also broadcastvia acetylcholine.
Overview of the autonomic (vegetative) nervous system
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Noradrenalin is aneurotransmitter inpostganglionic symphaticalendings.
Overview of the autonomic (vegetative) nervous system
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A wide range of neuro-transmittersis typical for neurons of themetasymphatic part of theautonomous department ofperipheral nervous system, soamong them we can distinguishholinergetic, adrenergic,serotoninergetic, peptidergetic andother neurons.
Overview of the autonomic (vegetative) nervous system
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In the organs with dual autonomicinnervation interaction functions ofsympathetic and parasympatheticnerves are observed in the form ofcaused effects antagonism.
Overview of the autonomic (vegetative) nervous system
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For example, stimulation of sympatheticnerves causes the narrowing of pupils,inhibition of peristalsis, sphincter relaxation,expansion of the bronchi and coronaryarteries, strengthening and acceleration theheart rate. Irritation of parasympatheticnerves leads to constriction of the pupil,increased peristalsis, sphincter closure, thenarrowing of the bronchi and coronaryarteries to slowing down and weakeningheartbeat.
Overview of the autonomic (vegetative) nervous system
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It should be emphasized that underthe conditions of autonomic and somaticbody functions as one integrated system,as sympathetic and parasympatheticnervous structures are widely used, sotheir functional synergy and antagonismare the two sides of the same process ofhomeostasis and homeokinesisregulation.
Overview of the autonomic (vegetative) nervous system
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Parasympathetic part
of the autonomic
department of the
peripheral nervous
system.
Overview of the autonomic (vegetative) nervous system
102
Parasympathetic part ofautonomous department of theperipheral nervous system isrepresented by preganglionic fibers,going together with III, VII, IX and Xpairs of cranial nerves and pelvicvisceral nerves, parasympathetic nodes( among which are two types:
1) extraorganic;
2) 2) intraorganic, as well as relevantpostganglionic fibers.
Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Extraorganic parasympatheticcomponents are located near bodiesinnervated. These include 5 largeparasympathetic nodes of the head(Ciliary wing-palatine, submandibular,sublingual-headed, ear) andparasympathetic pelvic nodes.
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Ciliar ganglion, g.ciliare,
has an uncertain shape and size (its
length in an average of 2 mm). This
node is located in the thickness of
fat tissue in the posterior part of the
eye socket on the outer surface of
the optic nerve.
Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Ciliary ganglion has three roots:
1) parasympathetic root, radix
parasympathica;
2) sympathetic root, radix
sympathica;
3) sensitive root, radix sensoria.
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Overview of the autonomic (vegetative) nervous system
Postganglionic parasympatheticfibers of ciliary unit consist ofshort ciliary nerves, nn.ciliaresbrevis, are sent to the eyeball,penetrate the sclera andinnervate ciliary muscle and irissphincter muscle.
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Overview of the autonomic (vegetative) nervous system
G.pterygopalatinum, near
to the size of 5 mm co-located in the pterygo-palatine fossa on the side of the pterygo-palatal opening.
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Postganglionic parasympathetic fibers wing-palatal node providing secretory gland innervation of the mucosa of the nasal cavity, mouth, pharynx and lacrimal gland.
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Overview of the autonomic (vegetative) nervous system
Pterygoplation ganglion has
three roots:
1) parasympathetic root, radix
parasympathica;
2) sympathetic root, radix
sympathica;
3) sensitive root, radix sensoria.
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Overview of the autonomic (vegetative) nervous system
Postganglionic parasympatheticfibers pterygo-palatal nodeprovides secretory glandinnervation of the mucosa in thenasal cavity, mouth, pharynxand lacrimal gland.
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Overview of the autonomic (vegetative) nervous system
Submandibular node, g.submandibulare, of about 3 mm, lies on the submandibular salivary gland under n.lingualis.
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Submandibular ganglion has
three roots:
1) parasympathetic root, radix
parasympathica;
2) sympathetic root, radix
sympathica;
3) sensitive root, radix sensoria.
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Overview of the autonomic (vegetative) nervous system
Postganglionic parasympatheticfibers submandibular nodeproviding secretory innervationsubmandibular and sublingualsalivary glands.
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Sublingual node,g.sublinguale, sometimes is
placed on the lateral surface ofsublingual salivary glands, butmore often is a cluster ofneurons along the branchesn.lingualis to sublingual gland.
Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Sublingual ganglion has three
roots:
1) parasympathetic root, radix
parasympathica;
2) sympathetic root, radix
sympathica;
3) sensitive root, radix sensoria.
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Overview of the autonomic (vegetative) nervous system
Postganglionic parasympatheticfibers of the sublingual nodeprovide secretory innervationto the sublingual gland.
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Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Ear node, g.oticum, of about 3 mm, located in the infratemporalfossa medially from the n.mandibularis under the oval hole.
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Overview of the autonomic (vegetative) nervous system
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Ear ganglion has three roots:
1) parasympathetic root, radix
parasympathica;
2) sympathetic root, radix sympathica;
3) sensitive root, radix sensoria.
Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Postganglionic parasympathetic fibers ear unit provide the secretory innervation of the parotid salivary gland.
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Pelvic nodes, gg.pelvica, are located in the lower part of hypogastric pelvic plexus and other vegetative plexus. Each has three roots:
1) ) parasympathetic root, radix
parasympathica;
2) sympathetic root, radix sympathica;
3) sensitive root, radix sensoria.
Overview of the autonomic (vegetative) nervous system
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Overview of the autonomic (vegetative) nervous system
Nn.splanchnici pelvici come from the front of branches II-IV sacral nerves (most of them are preganglionic parasympathetic fibers, less - sensitive) and provide parasympathetic and sensitive innervation of the pelvic organs and intestinal tract below the descending colon.
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Overview of the autonomic (vegetative) nervous system
The sympathetic part of the autonomous
department of the peripheral nervous
system
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Overview of the autonomic (vegetative) nervous system
The sympathetic part of the autonomous department of the peripheral nervous system is represented by preganglionic and postganglionic fibers and paravertebral (nodes sympathetic trunk) and prevertebralsympathetic nodes.
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Overview of the autonomic (vegetative) nervous system