Download central nervous system

NERVOUS SYSTEM
1. Classification of NS
2. CNS. Brain:
a) large hemispheres
b) cerebellum
3. CNS. Spinal cord
4. Meningeas
5. Blood-brain barrier
6. Peripheral nerve system.
Spinal ganglia
7. Peripheral nerve
8. Nerve endings
9. Autonomic nerve system
10. Simple reflex arch
Nervous system – special highly
organized system (nervous tissue +
connective)
–
intercommunicating
network of neurons
CLASSIFICATION
Anatomical (structural):
central nervous system (CNS)
– brain and spinal cord
peripheral (PNS) – endings,
fibers, ganglia, plexuses
Functional:
a) somatic (voluntary,
animal);
b) autonomic (involuntary,
vegetative)
FUNCTIONS
1. Integration
5. Conduction
2. Control 6. Analysis
3. Regulation
7. Response
4. Reception
NERVOUS SYSTEM ORIGIN
Ectoderm - nerve tube and ganglious lamella
Cranial portion of nerve tube – brain and sense
organs
Middle part of nerve tube and ganglious lamella–
spinal cord, dorsal-root ganglia (spinal ganglia),
autonomic ganglia and chromaffin tissue of
human body.
Nervous tube zones
Ependymal – precursors of glial ependymal cells
Mantial layer – neuroblasts (nerve cells) and
spongyoblasts (astrocytes and oligodendrocytes)
Marginal Zone – processes
BRAIN
Histologically: gray matter (nerve cells body)
white matter ( nerve fibers)
Gray matter: cortex + subcortical nuclei
MODUL – MFU of brain cortex
cilinder d 300 mkm around cortico-cortical
fiber
NEUROPIL – aggregations of nerve and glial
cells processes in central nerve system
Cytoarchitectonics - well prominent regular
location of nervous cells (6 layers)
Myeloarchitectonics - well prominent regular
location of nervous fibers (4 layers)
Cytoarchitectonics
Brain cortex has 6 layers
Pyramidal cells in the 2nd, 3rd, 4th,
5th layers
1. Molecular layer
2. Outer granular (10 mkm)
3. Pyramidal (10-40 mkm)
4. Inner granular layer
5. Ganglionic (120x80,
Bets, 1874)
6. Multiform layer
MYELOARCHITECTONICS
1. Above the 1st
2. Under the 1st
3. Above the 5th
4. Under the 5th
layer
layer
layer
layer
TYPES OF NERVE FIBERS
Associative
Comissural
Projective
52 FIELDS OF BRODMAN
GRANULAR CORTEX – sensory (2nd, 4th)
AGRANULAR CORTEX – motor (3rd,5th, 6)
CEREBELLUM
Functions: 1. Coordination
2. Movement
3. Balance
4. Muscle tone
Molecular layer: basket cells
large stellate cells
small stellate cells
Purkinje cells layer: Purkinje cells,
supporting cells (lophogliocytes)
Granular layer: corn cells
stellate cells (2types)
horizontal cells
CEREBELLUM
Afferent fibers:
Mosslike– from olives and
pons to the corn cells (tr.
olivocerebellaris,
tr. pontocerebellaris)
Climbing–from spinal cord and
vestibular nuclei to the
Purkinje cells
(tr. spinocerebellaris,
tr. vestibulocerebellaris)
Efferent fibers: axons of
Purkinje cells
Spinal cord
Spinal cord
Types of neurons:
Radicular
Funicular
Inner
Nuclei
Posterior horn: n. proprius,
n. thoracicus
Intermediate horn:
n.intermediolateralis
n.intermediomedialis
Anterior horn: 5 motor nuclei
MENINGEAS
MENINGEAS
3 protective coats of CNS: dura, arachnoid and pia
mater
Skull bone
Periosteum of skull
epidural space
1. DURA MATER – dense connective
tissue
epithelium
subdural space
2. ARACHNOID – flat epithelium
fibrocollagenous tissue
web-like strands
subarachnoid space
3. PIA MATER – squamous epithelium
– loose connective tissue with
blood vessels and nerve fibers
Basement membrane
Glia limitans (astrocytes)
Nerve tissue
BLOOD-BRAIN BARRIER
Prevents diffusion of substances
from the blood to the brain
Capillary wall
1. Endothelium
2. Basement membrane
3. Glial sheath (foot processes
of astrocytes)
Dorsal root ganglion
pseudounipolar cells
mantial cells
Peripheral nerve
Peripheral nerve
ultrastructure
NERVE ENDINGS
I SENSORY (receptors)
A. Disposition: 1. Interoceptors
2. Proprioceptors
3. Exteroceptors
B. Feelings: 1. Pain
2. Pressure
3. Temperature
C. Structure: 1. Simple (free)
2. Compound (nonfree):
encapsulated, noncapsulated
II SYNAPSES (chemical and electric)
– Structure
– Functions: excitatory, inhibiting
– Transmittor: acetylcholine, adrenalin,
bombesin …
III. EFFECTORY (effectors)
Motor
Secretory
SYNAPSES
Types of synapses
AUTONOMIC NERVE
SYSTEM
Anatomically: a) central
b) peripheral
Functionally: a) sympathetic
b) parasympathetic
SYMPATHETIC NS
1. Centers: thoracic-lumbar disposition
Nuclei intemediolateralis of spinal cord –
multipolar associative radicular neurons
2. Sympathetic ganglia: paravertebral (trunci
simpatici) and prevertebral (3)
PARASYMPATHETIC NS
1. Centers: cranio-sacral disposition
Nuclei of cranial nerves III, VII, IX and X
pairs
2. Extramural and intramural ganglia (Dogel
cells)
Autonomic nerve system
Autonomic ganglion
Golgi cells type I
type II
type III
Simple somatic reflex arch