NETTER’S - mementoslangues.fr · Netter’s Neuroscience Flash Cards Acknowledgments Netter’s Neuroscience Flash Cards, third edition, is a logical follow-up to Netter’s Atlas

NETTER’SNEUROSCIENCE

FLASH CARDS3rd Edition

D A V I D L . F E L T E N

Netter’s Neuroscience Flash Cards

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Acknowledgments

Netter’s Neuroscience Flash Cards, third edition, is a logical follow-up to Netter’s Atlas of Neuroscience, third edition. Both publications are intended to provide a visually oriented, succinct roadmap to the basic neurosciences and their application to human disease and its treatment. I have thoroughly enjoyed working with Marybeth Thiel (Senior Content Development Specialist), Elyse O’Grady (Senior Content Strategist), and John Casey (Senior Project Manager) from Elsevier in the long and challenging process of producing the Flash Cards and Atlas. Their helpfulness, diligence, professionalism, and commitment to bringing the Netter illustrations to yet more generations of physicians and health care professionals are inspirational. I thank Jim Perkins, the outstanding medical illustrator who worked closely with the authors of the third edition of Netter’s Atlas of Neuroscience; his skillful and accurate work have helped us to include extensive new information on molecular and cellular neurosciences. I also gratefully acknowledge the mentorship and wonderful teaching of former Professor Walle J.H. Nauta, MD, PhD, from the Massachusetts Institute of Technology; his superb organization of the nervous system, brilliant insights, and use of overviews inspired generations of neurosciences researchers, educators, and practitioners. I gratefully acknowledge the love, support, and encouragement of my wife, Dr. Mary Maida, who continues to tolerate mountains of books and papers piled all over the house and office while we worked on the Netter projects.

And finally, I acknowledge the inspiration that my mother, Jane E. Felten, provided through her long challenge with the aftermath of polio. Although she was badly crippled by the disease at the age of 8, she never let this neurological disease interfere with living a full and happy life. Her example demonstrates that human determination, will power, and faith can be powerful motivators for successful living, and that the indomitable human spirit can overcome even the most daunting challenges. Jane Felten demonstrated one of the fundamental principles of medicine—that one can be truly healed even in the face of severe pathology and disease and in the absence of a “cure.” She fought the good fight and lived a rich and rewarding life for more than 70 years. This project is dedicated to her memory.


Preface

Netter’s Neuroscience Flash Cards, third edition, consists of selected illustrations from Netter’s Atlas of Neuroscience, second edition, published in 2009. In this third edition I have deleted some of the previous flash cards and added many new ones from illustrations in the third edition of Netter’s Atlas of Neuroscience, published in 2016. Reference to the corresponding figure number in the Atlas can be found on the front of each card. Relevant structures are labeled on the front of each flash card illustration with 1, 2, 3 and so forth. On the back of the flash card is a list of all labeled structures. In some instances, such as the illustration of the cranial nerves, the schematic of hypothalamic nuclei, or the limbic forebrain structures, the labels are comprehensive enough to include all of the major components, providing students an opportunity to test their knowledge in a more thorough fashion than with just a few labels.

In addition to the list of labeled structures, the back of the flash card also includes a comment. The comments consist of two types of information: (1) organizational information about the illustration that provides a summary of the structure or system whose components are labeled on the front (e.g., a brief summary of visual system projections and their functional role on the flash card demonstrating the extent of retinal projections); (2) brief discussion of points of clinical relevance to the illustration on the front of the flash card. Approximately half of the flash cards have comments that address the former, and half have clinical comments. The choice of comments on the back was determined by the author’s consideration of what type of information would be most useful to a student trying to master the challenging field of neuroscience. Netter’s Atlas of Neuroscience, third edition, contains extensive clinical comments, in contrast to the first edition. For the more detailed clinical points, the Atlas itself is the appropriate source.

Students have the delightful habit of asking challenging questions related to illustrations—such as those used in Netter’s Atlas of Neuroscience, third edition—and include, “So how does this fit in with big picture of how the brain works?” or “So why do I need to know this information?” As information resources continue to expand, the ability of students to become more selective in their time allocation, to review helpful summaries of information that are still thorough and accurate, and to succinctly learn about the clinical relevance of information to patient care, becomes more and more valuable. These flash cards provide assistance toward that end. However, I also remind my students that they need to know the underlying basic science principles and mechanisms so that the clinical relevance is a logical follow-up, not just a bunch more facts to memorize.


In preparing the flash cards for the third edition, I also took into account the wonderful new technology that enables the student to obtain iPod or iPhone downloads, useful both for studying or exam preparation, and for reviewing information of relevance to a specific patient with a neurological problem or symptom. I tried to provide sufficiently comprehensive information in the labeling, as well as a useful succinct summary, to allow the student to review or refresh information that can be useful in the consideration of a patient’s diagnosis or evaluation.

The study of neuroscience ultimately requires the student to develop an understanding of the application of scientific knowledge to human illness and pathology. In medical school courses, clinical correlations and clinical examples are used to help students find the bridge between basic sciences and clinical application. Netter’s Atlas of Neuroscience, third edition, and Netter’s Neuroscience Flash Cards, third edition, have been written to optimize this process. Most students do not want to wallow through a 1,500 page textbook looking for relevant material buried in a seemingly endless discourse on esoterica. Until the student develops a solid overview of the field and is able to place structures, pathways, systems, symptoms, and neurological phenomena into proper context, the large reference works will be confusing and more trouble than they are worth. Most students want to cut to the chase and only later will they seek more detailed information when it becomes important in the care of a patient. These flash cards are designed to cut to the chase.

During my childhood, the use of flash cards was an enjoyable way to learn essential information and approaches. It is in this spirit that Netter’s Neuroscience Flash Cards were developed. Students who have the persistence and drive to use these cards to review fundamental neuroscience with a strong slant toward succinct organization and clinical relevance will emerge with a surprisingly broad array of knowledge about major neurological applications of the basic sciences. They also will find themselves unusually well prepared for licensure and board certification examinations that require such knowledge. I wish the users of these Flash Cards and Netter’s Atlas of Neuroscience, third edition, both success and enjoyment as they follow this visually-oriented learning format, and have the opportunity to benefit from the wonderful illustrations and medical knowledge of Dr. Frank Netter. It is the success of my students that makes the endeavor of teaching truly worthwhile.

David L. Felten, MD, PhD


Contents

Section 1 Overview of the Nervous System (64 cards)

Section 2 Regional Neuroscience (99 cards)

Section 3 Systemic Neuroscience (62 cards)

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Overview of the Nervous SystemPlates 1-1 to 1-64

1

1-1 Neuronal Structure

1-2 Neuronal Cell Types

1-3 Glial Cell Types

1-4 Astrocyte Biology

1-5 Microglial Biology

1-6 Stem Cells in the CNS: Intrinsic and Extrinsic Mechanisms

1-7 Blood-Brain Barrier

1-8 Inflammation in the CNS

1-9 Axonal Transport in the CNS and PNS

1-10 Myelination of CNS and PNS Axons

1-11 Synaptic Morphology

1-12 Conduction Velocity

1-13 Visual and Auditory Evoked Potentials

1-14 Neurotransmitter Release

1-15 Neuronal Signal Transduction Pathways

1-16 Foramina in the Base of the Adult Skull

1-17 Schematic of the Meninges and Their Relationships to the Brain and Skull

1-18 Hematomas

1-19 Surface Anatomy of the Forebrain: Lateral View

1-20 Lateral View of the Forebrain: Functional Regions

1-21 Anatomy of the Medial (Midsagittal) Surface of the Brain In Situ


Overview of the Nervous System Table of Contents

1 Overview of the Nervous SystemPlates 1-1 to 1-64

1-22 Anatomy of the Basal Surface of the Brain, with the Brain Stem and Cerebellum Removed

1-23 Brain Imaging: Computed Tomography Scans, Coronal and Sagittal

1-24 Brain Imaging: Magnetic Resonance Imaging, Axial and Sagittal T1-Weighted Images

1-25 Brain Imaging: Magnetic Resonance Imaging, Axial and Sagittal T2-Weighted Images

1-26 Horizontal Brain Sections Showing the Basal Ganglia

1-27 Major Limbic Forebrain Structures

1-28 Color Imaging of the Corpus Callosum by Diffusion Tensor Imaging

1-29 Hippocampal Formation and Fornix

1-30 Thalamic Anatomy

1-31 Thalamic Nuclei

1-32 Brain Stem Surface Anatomy: Posterolateral View

1-33 Brain Stem Surface Anatomy: Anterior View

1-34 Cerebellar Anatomy: Internal Features

1-35 Spinal Column: Bony Anatomy

1-36 Spinal Cord: Gross Anatomy In Situ

1-37 Spinal Cord: Its Meninges and Spinal Roots

1-38 Spinal Cord: Cross-Sectional Anatomy In Situ

1-39 Spinal Cord: White and Gray Matter

1-40 Ventricular Anatomy

Overview of the Nervous SystemPlates 1-1 to 1-64

1-41 Ventricular Anatomy in Coronal Forebrain Section

1-42 Anatomy of the Fourth Ventricle: Lateral View

1-43 Magnetic Resonance Imaging of the Ventricles: Axial and Coronal Views

1-44 Circulation of the Cerebrospinal Fluid

1-45 Arterial Supply to the Brain and Meninges

1-46 Common Sites of Cerebrovascular Occlusive Disease

1-47 Arterial Distribution to the Brain: Basal View

1-48 Arterial Distribution to the Brain: Cutaway Basal View Showing the Circle of Willis

1-49 Arterial Distribution to the Brain: Coronal Forebrain Section

1-50 Circle of Willis: Schematic Illustration and Vessels In Situ

1-51 Arterial Distribution to the Brain: Lateral and Medial Views

1-52 Magnetic Resonance Angiography: Coronal Full Vessel View

1-53 Vertebrobasilar Arterial System

1-54 Arterial Blood Supply to the Spinal Cord: Longitudinal View

1-55 Arterial Supply to the Spinal Cord: Cross-Sectional View

1-56 Meninges and Superficial Cerebral Veins

1-57 Venous Sinuses


Overview of the Nervous System Table of Contents

1-58 Magnetic Resonance Venography

1-59 Neurulation

1-60 Neural Tube Development and Neural Crest Formation

1-61 Development of Peripheral Axons

1-62 Early Brain Development: 36-Day-Old Embryo

1-63 Early Brain Development: 49-Day-Old Embryo and 3-Month-Old Embryo

1-64 Development of the Ventricles

Overview of the Nervous System

Neuronal Structure

1-1

12

3

4

5 6

7

891011


Neuronal Structure

See book 1.1

1. Dendrites2. Dendriticspines3. Roughendoplasmicreticulum4. Mitochondria5. Nucleus6. Axon7. Axonhillock8. Initialsegmentofaxon9. Neurotubules10. Golgiapparatus11. Cellbody(soma)

Comment: Theneuronisahighlyactivecellmetabolically,withgreatdemandsforoxygenandglucoserelatedtoaerobicmetabolism,especiallyimportantformaintainingiongradientsacrosstheneuronalcellmembrane.Neuronshaveverylittlemetabolicreserveanddependonmoment-to-momentdeliveryofoxygenandglucose.Neuronalformisrelatedtothefunctionofeachindividualneuron.Dendriticarborizationsreflecttheexpanseoftheneuronrelatedtogatheringsynapticinputfromotherneurons;thesearborizationsshowsomeplasticityandcanexpandorregress,dependingonthelocalneuronalmicroenvironmentandtheextentofinput.Theaxongenerallydistributestoarelativelyfixedsetofspecifictargetstructures(neurons,muscle,andeffectortissue)butalsomayexpandorregressasdictatedbydemand.Theinternalstateofgeneexpressionisasnapshotofthespecificdemandstowhichtheneuronisrespondingandmaychangeaccordingtohormonalorneurotransmittersignaling,oraccordingtoothermolecularinfluencesontranscriptionfactors.

Overview of the Nervous System 1-2

Neuronal Cell Types

12

11

10

9

87

6

3

4

5

1

2

CNS

PNS

Red: Motor neuron

Blue: Sensory neuron

Purple: Interneuron

Gray: Glial and neurilemmal cells and myelin

CNS: Central Nervous System

PNS: Peripheral Nervous System

Note: Cerebellarcells not shown here


Neuronal Cell Types

See book 1.4

1. Primarysensoryunipolarganglioncellofsensorycranialnerves2. Primarysensoryunipolarganglioncellofdorsalrootganglion3. Multipolarneuron(autonomicpreganglionicneuron)4. Autonomicganglioncell5. Schwanncell6. Motorendplate(neuromuscularjunction)7. Myelinsheath8. Myelinatedmotoraxon9. Multipolarneuron(spinalcordmotorneuron)10. Oligodendrocyte11. Astrocyte12. Multipolarneuron(pyramidalcell)

Comment: Neuronsareorganizedintohierarchies.Incoming(afferent)informationistransducedbysensoryreceptorsassociatedwiththedistalportionofprimarysensoryneurons.Theseneuronsconveytheinformationintothecentralnervoussystemandsynapseonsecondarysensoryneuronsassociatedwithreflexchannels,cerebellarchannels,andlemniscalchannels,thelatterofwhichisassociatedwithconsciousinterpretation.Outputsfromthecentralnervoussystemconsistof(1)lowermotorneurons,whoseaxonsterminateonskeletalmusclefibers,formingneuromuscularjunctions;and(2)preganglionicautonomicneuronsofthesympatheticandparasympatheticnervoussystems,whoseaxonssynapseonganglioncellsthat,inturn,regulatesmoothmuscle,cardiacmuscle,secretoryglands,metaboliccells,andcellsoftheimmunesystem.


Glial Cell Types

109

1

28

36

5

7 4


Glial Cell Types

See book 1.5

1. Microglialcell2. Oligodendrocyte3. Axon4. Perivascularpericyte5. Astrocyticfootprocess6. Astrocyte7. Piamatercells8. Neuron9. Tanycyte10. Ependymalcell

Comment: Glialcellsprovidethesupportivecellularstructureandfunctionforneurons.Theyactasscaffoldingbetweenneurons,sequesterions(potassium),insulatesynapticsites,providetrophicandmolecularsupportforneurons(astrocyticfunctions),providemyelinationofaxons(oligodendrocytefunction),phagocytizedebris,participateininflammatoryresponses,presentantigens,andprovideotherimmunologicandcytokinereactivity(microglialfunctions).Approximately10timesmoreglialcellsexistthanneurons.GlialcellsaretheprincipalcelltypesthatproliferatetoformCNStumors;neuronsrarelyformtumors.


Astrocyte Biology

100-200µmAstrocyte Physiology

Insulationof synapse

Ionicbalance

Neuron(not to scale)

Lactate

K+

K+

4

3

21

9

8

7 6

5


Astrocyte Biology

See book 1.6

1. Astrocyte3Ddomains2. Bushyastrocyteprocesses3. Metabolicsupport,ionicbalance(K+sequestration),growth

factorproduction,CNSgearformation4. Synapticmyelinationandisolation5. GlutamateandGABAreuptakefromasynapse6. Vascularsmoothmusclecell7. Astrocyticend-footprocess8. Vascularendothelialcell9. Gapjunctionbetweenastrocyteprocesses

Comment: Astrocytesprovidesupportandprotectionforneuronsandtheirprocesses,synapses,CNSvasculature,andtheinnermeningealpial-glialmembrane.Astrocyteprocessesformaninterdigitatingsyncytiumtoprotectsynapsesandexpandasend-footprocessestoprotecttheblood-brainbarrier.Astrocytesprovidemetabolicsupportforneurons,protecttheionicmilieu,uptakeandrecycleglutamateandGABA,andreleasegrowthfactorsandbioactivemolecules(gliotransmitters).AfteraCNSinjury,astrocytescanlaydownglialscartissue;thesescarsmayactasanirritatingfocusforprovokingseizures.Astrocytescanalsoundergotransformationandproliferationtoforminvasivetumors,astrocytomas.


Microglial Biology

“Resting” Microglia

Activated Microglia

Neuron(not to scale)Response to injury

or pathogens

Nucleus

Cell injury, apoptosis

DAMPs

PAMPs(bacterial LPS,viral RNA, etc.)

Pathogens

K+Ion flux

Release of:

Antigenpresentation

ATPfrom

damagedcells

NOD-like receptors(NLRs)

Purinergicreceptor-regulatedchannels

Pro-IL-1�Pro-IL-18

IL-1�IL-18

NF-�B, MAPKCaspase-1

ACTIVATION

T cell

4

3

2

1

6

5

Toll-like receptors(TLRs)


Microglial Biology

See book 1.7

1. Movingmicroglialprocesses2. Microglialprocesssamplingsynapse3. Synapticremodeling4. Reactiveoxygenspecies(•O2–),reactivenitrogenspecies(NO),

proinflammatorycytokines(IL-1,IL-6,TNF-α),matrixmetalloproteinases,neurotrophicfactors(NGF,TGF-β,neurotrophin4/5,GDNF,FGF)

5. Phagocytosisofpathogensandcellulardebris6. Tcellactivation(cytokines)

Comment: MicrogliaaremesenchymallyderivedcellsthatactasscavengercellsintheCNSandparticipateinimmunereactivityandinflammationintheCNS.MicrogliacanphagocytosecellulardebrisandpathogensandcanremodelandremovesynapsesindevelopingandadultCNS.Whenactivatedbyproinflammatorycytokinesorotherstimuli,microgliabecomeameboidinshapeandsecreteahostofreactivemolecules(oxygenspecies,NO,proinflammatorycytokines,matrixmetalloproteinases,andneurotrophicfactors).ActivatedmicrogliacanparticipateinandprovokeT-cellrelatedimmuneresponses,particularlyasTcellstraversetheCNS.


Stem Cells in the CNS: Intrinsic and Extrinsic Mechanisms

Transient amplifyingcells (C cells)

Olfactory bulb

Asymmetricdivision

Asymmetricdivision

Type IIprogenitor cells

Spatial and episodic memoryObject recognition memoryEmotional regulation

Myelin turnoverMyelin repair

NG2+ OPC

OPCs widely distributedthroughout adult brainand spinal cord (~5% ofall cells in CNS)

I. Subventricular zone (SVZ) of lateral ventricle

II. Subgranular zone (SGZ) of dentate gyrus

III. Oligodendrocyte progenitor cells (OPCs)

Ventricle

Ependyma

SVZ

4

3

2

1

6 7

8 9

10

11

12

5

Overview of the Nervous System See book 1.10

Stem Cells in the CNS: Intrinsic and Extrinsic Mechanisms

1. Superiorhornoflateralventricle2. Inferiorhornoflateralventricle3. Subventricularzone(SVZ)oflateralventricle4. Dentategyrusofhippocampus5. Subgranularzone(SGZ)ofdentategyrus6. Radialglia-likecells7. Neuroblastsandmigrationroute8. TypeIradialglia-likecells9. Maturegranulecellneuron10. Subgranularzone(SGZ)ofdentategyrus11. Granulecelllayer12. Molecularlayer

Comment: Indevelopment,neuronalstemcellsgiverisetowavesofproliferatingandmigratingneurons.Inadulthood,stemcellsarepresentinthesubventricularzoneofthelateralventriclesandcanformneuroblasts,whichcanmigratetositessuchastheolfactorybulborzonesofgranularneurons,providingadditionalneurons.Stemcellsinthesubgranularzonecangiverisetonewgranulecells.Oligodendroglialprogenitorcellscangiverisetonewoligodendrocytesinresponsetodemyelinatingprocessessuchasmultiplesclerosis.

Externallyderivedstemcellshavebeenusedexperimentallytotreatspinalcordinjury.Thesestemcellsareusedtoattempttoreplacedamagedneuronsorothercellsortoproducetrophicfactorsandgrowthfactorsthatstimulateintrinsicrepairandrecovery.


Blood-Brain Barrier

1

2

4

6

3

5


Blood-Brain Barrier

See book 1.12

1. Basementmembrane2. Astrocyticfootprocess3. Astrocyte4. Capillaryendothelialcell5. Tightjunctionofendothelialcells6. Capillarylumen

Comment: Themajoranatomicalsubstratefortheblood-brainbarrier(BBB)isthetightjunctionsofthecapillaryendothelialcells.TheyeffectivelykeeplargemoleculesoutoftheCNSandprotectthebrainfromadverseeffectsofcirculatingtoxinsandpotentiallydamagingmolecules.Somesubstancescandirectlycrossintothebrain,othershaveacompetitivefacilitatedtransport(someaminoacids),andothershaveanactivetransportsystemforingressintotheCNS.Atsitesofinflammation,tumors,trauma,andotherinsultstothebrain,theBBBmaybedisruptedandallowdamagingmoleculesintothebrain.TheeffectivenessoftheBBBpreventsmanytherapeuticagentsfromhavingdirectaccesstothebrainandrequiresintraventricularorintrathecaldeliveryorcouplingtoatransportcarrier.


Inflammation in the CNS

4

3

2

1

6

78

9

10

5

I. Response to intrinsic damage (e.g., acute stroke, trauma, bacterial infection, etc.)

II. Response to extrinsic stimuli (e.g., chronic disease)

III. Response to intrinsic proteinopathy or neurodegenerative process (e.g., Alzheimer disease)

Inflammatory Mediators

A. Rapid inflammatory response

TLRs

Tissue damage

Activated microglia

Extrinsic inflammatory stimulisuch as infection and chronicdisease (e.g., CVD, arthritis)acting via:1. Crossing blood-brain barrier2. Action on endothelium to produce prostaglandins3. Peripheral stimulation of the sensory part of the vagus n.

Age-related“priming”of microglia

Slow, chronic inflammationwith progressive synapticdysfunction and lossof neurons

Cytokines,chemokines

Activated microglia;Little or no

recruitment of peripheralblood elements

Ingestion of pathogensand cellular debris

Recruitment ofperipheral bloodelements (macrophages, neutrophils, T cells)

Cytokines/chemokines: IL-1 TNF� CCL2 TGF�ROS (e.g., superoxide)RNS (e.g., NO)Prostaglandins (e.g., PGE2)

ROS, RNS

Recruitment of peripheralblood elements

PGE2Cytokines,

chemokines,PGE2,

ROS, RNS

Pathogens

DAMPs

PAMPs

B. Delayed inflammatory response C. Healing


Inflammation in the CNS

See book 1.13

1. Cytokineandchemokineproduction2. Breakdownofblood-brainbarrier3. Neuronaldysfunctionandloss4. Astrocyticscarformation5. Activationoflocalmicroglia6. Neuronaldysfunctionandloss7. Microglialingestionofamyloid-β(Aβ)andtauprotein8. Aβplaque9. Tauneurofibrillarytangles10. Astrocytereactivityandloss

Comment: Inresponsetointrinsicdamage(e.g.,acutestroke,trauma,bacterialinfection),activatedmicrogliaandrecruitedperipheralbloodimmunocytescanprecipitateneuronaldysfunctionandlossandcanprovokeastrocytestolaydownscartissue.

Inresponsetoextrinsicstimuli(e.g.,infection,cardiovasculardisease,arthritis),activatedmicrogliaandrecruitedperipheralbloodelementscanproduceahostofinflammatorymediatorsthatprovokeneuronalinjuryandloss.

Duringanintrinsicproteinopathyorneurodegenerativeprocess(e.g.,Alzheimerdisease),chronicallyactivatedmicrogliacaningestanddegradeamyloidβ(fromAβplaques)andtauproteinfromneurofibrillarytangles,provokingastrocytereactivityandloss,andchronicinflammationwithsynapticdysfunctionandneuronalloss.

RetrospectivestudiesinpatientswithchronicarthritishaveshownthatprolongedingestionofantiinflammatorydrugsreducesthelikelihoodofAlzheimer-relateddysfunction.ProspectivestudieshavenotbeensuccessfulatreducingthelikelihoodofAlzheimerdiseaseanditscognitivedysfunction,probablyduetothelong-standingdurationofpathologyandchronicinflammationbythetimesymptomsbecomeevidentandprospectivetherapyisinitiated.


Axonal Transport in the CNS and PNS

Nucleus

Nucleus

Nucleus

100–400mm/day in a saltatory fashion (start-stop-start)

Microtubule

Cargo includes: - Synaptic vesicles and synaptic vesicle precursors - Mitochondria and other membrane organelles - Integral membrane proteins - Secretory polypeptides - Neurotransmitters - Elements of smooth endoplasmic reticulum

200–270mm/day

Cargo includes: - Endosomes - Damaged mitochondria and other organelles - Elements of smooth endoplasmic reticulum - Regulatory signals (growth factors and neurotrophins) - Viruses and toxins (e.g., tetanus, herpes simplex, rabies, polio)

Different substances move attwo different speeds:

Slow Component a (SCa)0.2–2.5mm/day (rate of neurite elongation) - Microtubules - Neurofilaments - Cytoskeletal proteins (e.g., � and � tubulin)

Slow Component b (SCb)5.0–6.0mm/day - Cytosolic proteins - Clathrin - Calmodulin - Soluble enzymes and other proteins

I. Fast Anterograde Axonal Transport

II. Fast Retrograde Axonal Transport

III. Slow Axonal Transport (Anterograde Only)

4

321

6 7

8 9

10

5


Axonal Transport in the CNS and PNS

See book 1.14

1. Vesicle2. Kinesin3. Membraneorganelles4. Microtubule5. Dynein6. Damagedorganelles7. Endosome8. Neurofilamentsmoveonownorcarriedalongmicrotubules9. Shortsegmentsofmicrotubulescarriedbydynein10. Pre-assemblyofmicrotubulesegments

Comment: Neuronstransportproteins,organelles,andothermaterialsinbothdirectionsbetweenthecellbodyandnerveterminals.Fastanterogradeaxonaltransport,fromcellbodytonerveterminals,proceedsinastart-stop(saltatory)fashion,transportingsynapticvesicles,mitochondria,andorganelles,smoothER,integralmembraneproteins,secretorypolypeptides,andsomeneurotransmitters.Fastretrogradeaxonaltransport,fromnerveterminalstothecellbody,transportsendosomes,damagedorganelles,growthfactorsandotherproteins,viruses,andtoxins.Poliovirustakesadvantageofthisprocesstoinvade,damage,andsometimeskilllowermotorneurons.Slowanterogradeaxoplasmictransport,withtwoseparatecomponents,transportsmicrotubulesandneurofilaments,cytosolicandcytoskeletalproteins,calmodulin,andotherlargemolecules.Thisslowprocessisessentialfordamagedaxonstoregrowandreestablishtheirconnectionsafterinsultorinjury;asaconsequence,suchaxonalrecoveryproceedsatarateofapproximately1mm/day.


Myelination of CNS and PNS Axons

6

8

7

5

4

2 3

Peripheral Nervous SystemCentral Nervous System

1

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NETTER’S - mementoslangues.fr · Netter’s Neuroscience Flash Cards Acknowledgments Netter’s Neuroscience Flash Cards, third edition, is a logical follow-up to Netter’s Atlas