Neural - Spinal Cord Development

From Embryology
Embryology - 17 Nov 2017    Facebook link Pinterest link Twitter link  Expand to Translate  
Google Translate - select your language from the list shown below (this will open a new external page)

العربية | català | 中文 | 中國傳統的 | français | Deutsche | עִברִית | हिंदी | bahasa Indonesia | italiano | 日本語 | 한국어 | မြန်မာ | Pilipino | Polskie | português | ਪੰਜਾਬੀ ਦੇ | Română | русский | Español | Swahili | Svensk | ไทย | Türkçe | اردو | ייִדיש | Tiếng Việt    These external translations are automated and may not be accurate. (More? About Translations)

Stage10 sem6.jpg

Introduction

Neural groove closing to neural tube
Embryo early week 4 (Stage 10)
Spinal cord transverse section week 8
Spinal cord transverse section
Embryo week 8 (Stage 22)

Neural development is one of the earliest systems to begin and the last to be completed after birth. This development generates the most complex structure within the embryo and the long time period of development means in utero insult during pregnancy may have consequences to development of the nervous system.

The early central nervous system begins as a simple neural plate that folds to form a groove then tube, open initially at each end. Failure of these opening to close contributes a major class of neural abnormalities (neural tube defects).

Within the neural tube stem cells generate the 2 major classes of cells that make the majority of the nervous system : neurons and glia. Both these classes of cells differentiate into many different types generated with highly specialized functions and shapes. This section covers the establishment of neural populations, the inductive influences of surrounding tissues and the sequential generation of neurons establishing the layered structure seen in the brain and spinal cord.

  • Neural development beginnings quite early, therefore also look at notes covering Week 3- neural tube and Week 4-early nervous system.
  • Development of the neural crest and sensory systems (hearing/vision/smell) are only introduced in these notes and are covered in other notes sections.


Neural Links: Introduction | Ventricular System | Stage 22 | Gliogenesis | Fetal | Medicine Lecture - Neural | Lecture - Ectoderm | Lecture - Neural Crest | Lab - Early Neural | Neural Crest | Sensory | Abnormalities | Folic Acid | Iodine Deficiency | Fetal Alcohol Syndrome | Postnatal | Postnatal - Neural Examination | Histology | Historic Neural | Category:Neural
Human embryo (Carnegie stage 13) spinal cord (shown in cross-section at the bottom of image).

Some Recent Findings

  • Coordination of progenitor specification and growth in mouse and chick spinal cord[1] "Our data show that domain proportions are first established by opposing morphogen gradients and subsequently controlled by domain-specific regulation of differentiation rate but not differences in proliferation rate. Regulation of differentiation rate is key to maintaining domain proportions while accommodating both intra- and interspecies variations in size. Thus, the sequential control of progenitor specification and differentiation elaborates pattern without requiring that signaling gradients grow as tissues expand."
  • Motor neuron position and topographic order imposed by β- and γ-catenin activities[2] "Neurons typically settle at positions that match the location of their synaptic targets, creating topographic maps. In the spinal cord, the organization of motor neurons into discrete clusters is linked to the location of their muscle targets, establishing a topographic map of punctate design. To define the significance of motor pool organization for neuromuscular map formation, we assessed the role of cadherin-catenin signaling in motor neuron positioning and limb muscle innervation. We find that joint inactivation of β- and γ-catenin scrambles motor neuron settling position in the spinal cord but fails to erode the predictive link between motor neuron transcriptional identity and muscle target. Inactivation of N-cadherin perturbs pool positioning in similar ways, albeit with reduced penetrance. These findings reveal that cadherin-catenin signaling directs motor pool patterning and imposes topographic order on an underlying identity-based neural map."
  • Dynamic imaging of mammalian neural tube closure[3]
More recent papers
Mark Hill.jpg
PubMed logo.gif

This table shows an automated computer PubMed search using the listed sub-heading term.

  • Therefore the list of references do not reflect any editorial selection of material based on content or relevance.
  • References appear in this list based upon the date of the actual page viewing.

References listed on the rest of the content page and the associated discussion page (listed under the publication year sub-headings) do include some editorial selection based upon both relevance and availability.

Links: References | Discussion Page | Pubmed Most Recent | Journal Searches


Search term: Spinal Cord Embryology

Pere Boadas-Vaello, Judit Homs, Marta Portero-Tresserra, Beltrán Álvarez-Pérez, Meritxell Deulofeu, Enrique Verdú Graded photochemical spinal cord injury results in chronic hyperalgesia and depression-like behaviour but no anxiety exacerbation in female BALB/c mice. Neurosci. Lett.: 2017; PubMed 29126777

Okan Ozkunt, Kerim Sariyilmaz, Halil Can Gemalmaz, Seren Gülsen Gürgen, Ulaş Yener, Fatih Dikici Investigation of efficacy of treatment in spinal cord injury: Erythropoietin versus methylprednisolone. J Orthop Surg (Hong Kong): 2017, 25(3);2309499017739481 PubMed 29121822

Yanchun Chen, Qing Wang, Qiaozhen Wang, Huancai Liu, Fenghua Zhou, Yawen Zhang, Meng Yuan, Chunyan Zhao, Yingjun Guan, Xin Wang DDX3 binding with CK1ε was closely related to motor neuron degeneration of ALS by affecting neurite outgrowth. Am J Transl Res: 2017, 9(10);4627-4639 PubMed 29118923

Ting Tian, Zhenhai Yu, Naili Zhang, Yingwei Chang, Yuqiang Zhang, Luping Zhang, Shuai Zhou, Chunlei Zhang, Guoying Feng, Fei Huang Modified acellular nerve-delivering PMSCs improve functional recovery in rats after complete spinal cord transection. Biomater Sci: 2017; PubMed 29106428

Banafsheh Nikmehr, Mahshid Bazrafkan, Gholamreza Hassanzadeh, Abdolhossein Shahverdi, Mohammad Ali Sadighi Gilani, Sahar Kiani, Tahmineh Mokhtari, Farid Abolhassani The Correlation of Gene Expression of Inflammasome Indicators and Impaired Fertility in Rat Model of Spinal Cord Injury: A Time Course Study. Urol J: 2017, 14(6);5057-5063 PubMed 29101761

Neural Development Overview

Neuralation begins at the trilaminar embryo with formation of the notochord and somites, both of which underly the ectoderm and do not contribute to the nervous system, but are involved with patterning its initial formation. The central portion of the ectoderm then forms the neural plate that folds to form the neural tube, that will eventually form the entire central nervous system.

Early developmental sequence: Epiblast - Ectoderm - Neural Plate - Neural groove and Neural Crest - Neural Tube and Neural Crest


Neural Tube Primary Vesicles Secondary Vesicles Adult Structures
week 3 week 4 week 5 adult
neural plate
neural groove
neural tube

Brain
Prosencephalon Telencephalon Rhinencephalon, Amygdala, Hippocampus, Cerebrum (Cortex), Hypothalamus, Pituitary | Basal Ganglia, lateral ventricles
Diencephalon Epithalamus, Thalamus, Subthalamus, Pineal, third ventricle
Mesencephalon Mesencephalon Tectum, Cerebral peduncle, Pretectum, cerebral aqueduct
Rhombencephalon Metencephalon Pons, Cerebellum
Myelencephalon Medulla Oblongata
Spinal Cord

Early Brain Vesicles

In week 3, the neural plate forms and the caudal end of the neural plate remains narrow compared to the cranial end which rapidly expands.

In week 4, when the plate folds to form the neural tube, the cranial end of the tube then forms a series of enlarged cavities (vesicles) that will eventually form the brain. The caudal end of the tube forms a narrower tube of relatively the same size along its length that will eventually form the spinal cord.

Primary Vesicles Secondary Vesicles
CNS primary vesicles.jpg CNS secondary vesicles.jpg
early embryonic late embryonic

Human brain growth 01.jpg

Direct comparison of brain growth embryonic and fetal period. Note the relative size of the spinal cord seen at the lower end of each image.

Spinal Cord Regions

The neural tube forms similar regions around the wall along its length, including the spinal cord. The floor and roof plate are specialised developmental regions, important embryonic "patterning" regions.[4]

  • Floor plate - thin wall region that overlies the notochord. Ventral patterns the spinal cord, both floor plate and notochord produce Sonic hedgehog (Shh) (see also Notochord)
  • Basal plate - thick wall region lying either side of the floor floor plate. The ventral horn motor neurons develop here and extend axons out of the spinal cord to innervate developing skeletal muscle. Tracts formed by axons surround these horns and project both up and down the spinal cord.
  • Alar plate - thick wall region lying either side of the roof floor plate. The sensory dorsal horn develops there and receives axons from the sensory structures outside the spinal cord. The adult horn is divided into 6 laminae (I to VI). Tracts formed by axons surround these horns and project both up and down the spinal cord.
  • Roof plate - thin wall region that underlies the dorsal ectoderm epithelium. Dorsal patterns the spinal cord, the roof plate produces Bone morphogenetic proteins (BMPs). [5][6]
  • Lumen - neuroepithelium lined fluid-filled space continuous with the brain ventricular system.
Week 4 Week 8
Stage13 spinal cord02.jpg Human Stage22 spinal cord02.jpg
Stage 13 Spinal cord cross-section (upper part of cord).
labeled image | unlabeled image
Stage 22 Spinal cord cross-section (ventral is at bottom of image)
labeled image | unlabeled image

Embryonic Development

Week 4

Spinal cord cross-section (upper part of cord) (Carnegie Stage 13)
Stage13 spinal cord01.jpg Stage13 spinal cord02.jpg

Week 8

Human Stage22 spinal cord02.jpg

Virtual Slide

Stage 22 - Spinal Cord (rotated)

Human Stage22 spinal cord03.jpg

 ‎‎Mobile | Desktop | Original

Stage 22 | Embryo Slides
These listed features link to zoomed views of the virtual slide with the named feature generally in the centre of the view.

Use the (-) at the top left of the screen to see where this feature is located.

Spinal Cord Features Other Features

Fetal Development

Links: Fetal Development

Conus Medullaris

Human week 10 fetus
Conus Medullaris (week 10, GA week 12)

The conus medullaris (Latin, "medullary cone") is the tapered, lower end of the spinal cord. An ultrasound study of the position of the spinal cord conus medullaris at 18-22 weeks (20 to 24 weeks ((GA}}) showed that it ended adjacent to vertebrae L2, L2-3 vertebral space, and L3 (73/78, 93%).[7]


Plexus Development

The spinal nerves initially leave the spinal cord at each individual segmental levels. At various levels they then form an intersecting network of nerves, a plexus, from which mixed segmental nerves emerge.


Cervical Plexus

Adult Cervical Plexus
Gray0804.jpg

(plexus cervicalis)

  • formed by the anterior divisions of the upper four cervical nerves
  • each nerve, except the 1st, divides into an upper and a lower branch, and the branches unite to form three loops.
  • branches are divided into two groups, superficial and deep.

Search PubMed: cervical plexus embryology

Brachial Plexus

Adult Brachial Plexus
Gray0807.jpg

plexus brachial

  • plexus extends from the lower part of the side of the neck to the axilla.
  • nerves that form it are similar in size, mode of communication is subject to some variation.
  • formed by union of the anterior divisions of the lower 4 cervical nerves and the greater part of the anterior division of the first thoracic nerve.
  • 4th cervical usually gives a branch to the 5th cervical.
  • 1st thoracic frequently receives one from the 2nd thoracic.
Search PubMed: brachial plexus embryology

Lumbar Plexus

Adult Lumbar Plexus
Gray0822.jpg

plexus lumbalis

  • formed by anterior divisions of the first three and the greater part of the 4th lumbar nerves.
  • 1st lumbar often receives a branch from the last thoracic nerve.
Search PubMed: lumbar plexus embryology

Sacral Plexus

Dermatomes

A dermatome represents the area of skin that is mainly supplied by a single spinal nerve. Therefore each spinal nerve can be "mapped" to a region of the external body surface and that this "map" is established before embryonic limb rotation.


Links: Sensory - Touch Development | Limb Development

Molecular

Neural tube dorsoventral patterning SHH BMP.jpg|

Neural tube Dorsoventral Patterning by SHH BMP[8]

Dorsoventral domains are established by opposing concentration gradients of Sonic Hedgehog (Shh) and Bone Morphogenic Protein (BMP).

  • left - These regulate progenitor gene expression. The progenitor genes cross-repress each other to establish domain boundaries.
  • right - Each domain will give rise to a specific cell type that expresses various post-mitotic differentiation genes.


Links: SHH | BMP

Spinal Cord Histology

Identify gray and white matter, central canal (surrounded by ependymal cells), dorsal and ventral horns, meninges (pia, arachnoid and dura mater), subarachnoid space with dorsal and ventral rootlets, blood vessels, a motor neurone with a cell body (soma), nucleus, nucleolus, Nissl granules, an axon with axon hillock area, dendrites, glial cells (oligodendrocytes, astrocytes).

Spinal cord (Luxol Fast Blue)
Spinal cord histology 01.jpg Spinal cord histology 02.jpg
Spinal cord - Grey and white matter
Spinal cord histology 03.jpg Spinal cord histology 04.jpg
Spinal cord - Grey matter
Spinal cord histology 11.jpg

Grey matter (HE)

Spinal cord histology 12.jpg

Grey matter (silver)

Spinal Cord: Overview 1 | Overview 2 | Overview animation | Grey matter | Grey matter | Grey matter | White matter | Overview unlabeled | Grey matter unlabeled 1 | Grey matter unlabeled 2 | White matter unlabeled 1 | Ependymal cells unlabeled


Spinal cord histology 10.jpg
Mouse ependymal cilia 01-icon.jpg
 ‎‎Ependymal cilia
Page | Play
The media player is loading...


Additional Images

Historic

Historic Disclaimer - information about historic embryology pages 
Mark Hill.jpg
Pages where the terms "Historic Textbook" and "Historic Embryology" appear on this site, and sections within pages where this disclaimer appears, indicate that the content and scientific understanding are specific to the time of publication. This means that while some scientific descriptions are still accurate, the terminology and interpretation of the developmental mechanisms reflect the understanding at the time of original publication and those of the preceding periods, these terms and interpretations may not reflect our current scientific understanding.     (More? Embryology History | Historic Embryology Papers)
Filum Terminale (1919)
Streeter GL. Factors involved in the formation of the filum terminale. (1919) Amer. J Anat. 22:1-11.
Human Embryology And Morphology (1921)
Keith, A. Human Embryology And Morphology (1921) Longmans, Green & Co.:New York.

7 Spinal Cord

Anatomy of the Human Body (1918)
Gray, H. Anatomy of the Human Body. Philadelphia: Lea & Febiger, 1918.

References

  1. Anna Kicheva, Tobias Bollenbach, Ana Ribeiro, Helena Pérez Valle, Robin Lovell-Badge, Vasso Episkopou, James Briscoe Coordination of progenitor specification and growth in mouse and chick spinal cord. Science: 2014, 345(6204);1254927 PubMed 25258086
  2. Elena Y Demireva, Lawrence S Shapiro, Thomas M Jessell, Niccolò Zampieri Motor neuron position and topographic order imposed by β- and γ-catenin activities. Cell: 2011, 147(3);641-52 PubMed 22036570
  3. Christina Pyrgaki, Paul Trainor, Anna-Katerina Hadjantonakis, Lee Niswander Dynamic imaging of mammalian neural tube closure. Dev. Biol.: 2010, 344(2);941-7 PubMed 20558153
  4. Leigh Wilson, Malcolm Maden The mechanisms of dorsoventral patterning in the vertebrate neural tube. Dev. Biol.: 2005, 282(1);1-13 PubMed 15936325
  5. Victor V Chizhikov, Kathleen J Millen Mechanisms of roof plate formation in the vertebrate CNS. Nat. Rev. Neurosci.: 2004, 5(10);808-12 PubMed 15378040
  6. Victor V Chizhikov, Kathleen J Millen Roof plate-dependent patterning of the vertebrate dorsal central nervous system. Dev. Biol.: 2005, 277(2);287-95 PubMed 15617675
  7. Yuri Perlitz, Ido Izhaki, Moshe Ben-Ami Sonographic evaluation of the fetal conus medullaris at 20 to 24 weeks' gestation. Prenat. Diagn.: 2010, 30(9);862-4 PubMed 20582935
  8. 26499851</pubmed>| Neural Dev.

Reviews

Nicholas D E Greene, Andrew J Copp Development of the vertebrate central nervous system: formation of the neural tube. Prenat. Diagn.: 2009, 29(4);303-11 PubMed 19206138

Fausto Ulloa, Elisa Martí Wnt won the war: antagonistic role of Wnt over Shh controls dorso-ventral patterning of the vertebrate neural tube. Dev. Dyn.: 2010, 239(1);69-76 PubMed 19681160

Jeremy S Dasen, Thomas M Jessell Hox networks and the origins of motor neuron diversity. Curr. Top. Dev. Biol.: 2009, 88;169-200 PubMed 19651305

Eric Dessaud, Andrew P McMahon, James Briscoe Pattern formation in the vertebrate neural tube: a sonic hedgehog morphogen-regulated transcriptional network. Development: 2008, 135(15);2489-503 PubMed 18621990

Bradley J Molyneaux, Paola Arlotta, Jeffrey D Macklis Molecular development of corticospinal motor neuron circuitry. Novartis Found. Symp.: 2007, 288;3-15; discussion 15-20, 96-8 PubMed 18494249

O A Glenn, A J Barkovich Magnetic resonance imaging of the fetal brain and spine: an increasingly important tool in prenatal diagnosis, part 1. AJNR Am J Neuroradiol: 2006, 27(8);1604-11 PubMed 16971596

O A Glenn, J Barkovich Magnetic resonance imaging of the fetal brain and spine: an increasingly important tool in prenatal diagnosis: part 2. AJNR Am J Neuroradiol: 2006, 27(9);1807-14 PubMed 17032846

T W Sadler Embryology of neural tube development. Am J Med Genet C Semin Med Genet: 2005, 135C(1);2-8 PubMed 15806586

Marysia Placzek, James Briscoe The floor plate: multiple cells, multiple signals. Nat. Rev. Neurosci.: 2005, 6(3);230-40 PubMed 15738958


Articles

Hirotomo Saitsu, Kohei Shiota Involvement of the axially condensed tail bud mesenchyme in normal and abnormal human posterior neural tube development. Congenit Anom (Kyoto): 2008, 48(1);1-6 PubMed 18230116


Books

Search PubMed

November 2010 search "Spinal Cord Embryology" All (7631) Review (641) Free Full Text (1562)

Search Pubmed: Spinal Cord Embryology | Spinal Cord Development



Glossary Links

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols


{Footer}}