Review of Spinal Cord

with

Basics of Neuroanatomy

Brain Meninges

Prof. D.H. Pauža

Parts of Nervous System

Review of Spinal Cord

with

Basics of Neuroanatomy

Brain Meninges

Prof. D.H. Pauža

Neurons and Neuroglia

Neuron Body (soma)

Perikaryon

Nissl substance or Tigroid

Dendrites

Axon

Myelin

Terminals

Synapses

Human brain contains per

1011-12 (trillions) neurons

Unipolar, pseudounipolar, bipolar, multipolar

Afferent (sensory, centripetal)

Efferent (motor, centrifugal, effector)

Associate (interneurons)

Neuronal types

Synapse

In human brain – neurons 1011 (100 trillions)

Synapses – 1015 (quadrillions)

Presynaptic membrane

Postsynaptic membrane, receptors

Synaptic cleft

Synaptic vesicles, neuromediator

Mitochondria

Neuromediators •Acetylcholine

•Noradrenaline

•Serotonin

•GABA

•Endorphin

•Encephalin

•P substance

•Neuronal nitric oxide

Adrenergic nerve ending. There are many 50-nm-diameter

vesicles (arrow) with dark, electron-dense cores containing

norepinephrine. x40,000.

Cell Types of Neuroglia Astrocytes - Oligodendrocytes – Ependimocytes - Microglia

Astrocytes – a part of hemoencephalic barrier

Oligodendrocytes

Ependimocytes and

microglial cells

Microglia represent the endogenous brain defense and immune system,

which is responsible for CNS protection against various types of

pathogenic factors. After invading the CNS, microglial precursors

disseminate relatively homogeneously throughout the neural tissue and

acquire a specific phenotype, which clearly distinguish them from their

precursors, the blood-derived monocytes.

The ´resting´ microglia are the fastest moving cells in the brain

PNS

Neuronal lemmocytes (Schwann cells)

Nerve fiber: myelinated and unmyelinated

Impulse propagation speed: 0,5-120 m/s

A, B, C types of nerve fibers

CNS

Neuroglia in peripheral nervous system

Parts of Nervous System

General definitions in

neuroanatomy

Meninges on spinal cord Dura mater, arachnoid and pia mater Epidural and subdural spaces

Meninges on spinal cord Dura mater, arachnoid and pia mater Epidural and subdural spaces

Meninges on brain: Dura mater, arachnoid and pia mater

Meninges on brain: Dura mater, arachnoid and pia mater

Meninges on Brain: Dura mater, arachnoid and pia mater Falx cerebri and Tentorium cerebeli

Venal sinuses

Meninges on Brain: Dura mater, arachnoid and pia mater

Arachnoid villi, granulationes arachnoideae

Meninges: Dura mater, arachnoid and pia mater

Meninges: Dura mater, arachnoid and pia mater

Cisterna magna or

cerebellomedulary cisterna

Interpedicular cisterna

Subarachnoidal space

Liquor or cerebrospinal fluid (CSF)

Central canal and Brain ventricles Lateral, Third and Fourth

Interventricular foramen

Cerebral aqueduct

Lateral and median apertures 4th ventricle

Choroid plexus and Tela charoidea

Cerebrospinal fluid

Choroid plexus and Tela charoidea

Cerebrospinal fluid

Neuronal organization

CNS:

Grey matter: nuclei and cortex, functional nuclei White matter: pathways, fascicles

Neuronal organization

PNS: Ganglia and nerves

Internal structure

White matter: pathway (tractus), loop (lemniscus, ansa), decussatio, chiasma,

stria.

Anatomy of Spinal Cord

Anatomy of Spinal Cord Conus medularis up to L2

Filum terminale

Spinal cord Conus medularis, L2

Filum terminale

SPINAL CORD

External anatomy Cervical and lumbar enlargements;

Anterior median fissure,

Posterior median groove or sulcus,

Posterior and anterior lateral sulci.

SPINAL CORD

External anatomy

Anterior (motor) and posterior (sensory) spinal nerve roots,

Spinal ganglion or dorsal root ganglion,

Spinal nerve and its anterior and posterior branches .

Cauda equina

SPINAL CORD

External anatomy

Segments of spinal cord

C1-8

Th1-12

L1-5

S1-5

Co1

INTERNAL ANATOMY OF SPINAL CORD Central canal;

Grey matter: anterior3, posterior4 and lateral5 horns and columns

(in lat., cornua anteriora, posteriora et laterale; columna anteriora, posteriora et intermedia),

Central intermedial substance

(in lat., substantia intermedia seu gelatinosa centralis)

Pars cervicalis Pars thoracica Pars lumbalis

INTERNAL ANATOMY OF SPINAL CORD

Grey matter: anterior, posterior and lateral horns and columns (cornua anteriora,

posteriora et laterale; columna anteriora, posteriora et intermedia)

Principal Neuronal Organization in Spinal Cord

I

IV

VII

VIII

X

IX

Nucleus proprius, Sensation of skin

Sub.gelatinosa,

Pain and temperature

signal transmission nucleus

Nucleus marginalis, Pain

and temperature

signal transmission nucleus

INTERNAL ANATOMY OF SPINAL CORD

Grey matter:

nuclei and/or laminae by Bror Rexed

Nucleus intermediomedianalis Sensation of internal organs

Nucleus dorsalis

(C8-L2) basilaris. Proprioreception of the upper

and lower limbs

Nucleus

intermediolateralis

Sympathetic nucleus

(S2-4: Nucl.parasympathicus).

(Parasympathetic) V VI

Nuclei

posteromedialis

et centralis. Associate neurons and

descending pathways

interaction nucleus

Nuclei mediales et laterales. Motor nucleus of muscles of trunk and

limbs

Substantia intermedia centralis.

Nucleus of commissural neurons composing

commissura alba

Bror Rexed (June 19, 1914 - August 21, 2002) was a Swedish neuroscientist and professor

at Uppsala University. Internationally, he is best known today for his development

of the system now known as Rexed laminae.

Rexed B (1952). "The cytoarchitectonic organization of the spinal cord in the cat.".

J Comp Neurol 96 (3): 414-95.

SPINAL CORD L AMINAE BY BROR REXED

GREY MATTER NUCLEAR ORGANIZATION OF SPINAL NEURONS

GREY MATTER NUCLEAR ORGANIZATION OF SPINAL NEURONS

INTERNAL ANATOMY OF SPINAL CORD

White matter: anterior, posterior and lateral funiculae

(funiculus anterior, lateralis et posterior)

White matter Anterior, posterior and lateral funiculae; Funiculus anterior, lateralis et posterior.

Ascending and descending pathways;

Funiculus proprius

INTERNAL ANATOMY OF SPINAL CORD

White matter: anterior, posterior and lateral funiculae

(funiculus anterior, lateralis et posterior)

Ascending and descending pathways; funiculus proprius

Internal anatomy.

White matter: ascending-afferent pathways

Gracile fasciculus – tactile and proprioceptive sensations

Cuneate fasciculus - tactile and proprioceptive sensations

Spinothalamic tracts – pain and temperature sensation

Spinocerebellar tracts – proprioceptive sensation

Pyramidal and extra-

pyramidal pathways

Lateral and anterior pyramidal tracts- striated muscles

Rubrospinal tract – cerebellum and extrapyramidal system

Tectospinal tract – unconditioned reflexes of skeletal muscles related to vision and hearing

Vestibulospinal tract – regulation of equilibrium (balance)

Internal anatomy.

White matter: descending-efferent pathways