Nerve TissueNerve Tissue

赵慧赵慧

Department of Histology & EmbryologyDepartment of Histology & Embryology

Jilin UniversityJilin University

Nerve tissue

Hui Zhao

General Description

Nerve Cell (Neuron)

•Receive stimulation•Integrate message•Conduct the nerve impulse

Nerve Tissue

Neuroglial Cell(Neuroglia)

•Support•Nourish•Insulate•Protect•Repair

Nerve tissue

Hui Zhao

Contents

NeuronNeuron1

SynapseSynapse2

NeurogliaNeuroglia3

Nerve Fiber and NerveNerve Fiber and Nerve4

Nerve EndingNerve Ending5

Nerve tissue

Hui Zhao

I. Neuron

1. SomaCell membraneNucleus Cytoplasm

2. ProcessDendriteAxon

胞体

Nerve tissue

Hui Zhao

1. Soma

Cell membraneExcitable membrane, receiving stimutation, forming and conducting nerve impulesReceptor; Voltage-gated channel; Chemically-gated channel

Nucleus: spherical, large, centrally-located, pale-stainingCytoplasm (Perikaryon): Nissl body; Neurofibril; Lipofuscin

Nissl body

Dendrite

Axon

Dendrite

NucleusNucleolus

Axon hillock

Nerve tissue

Hui Zhao

1. Soma

Nissl body (Chromophilsubstance, tigroid body)

LM: basophilic mass or granulesEM: RER, free ribosomeFunction: produce protein, enzyme and neurotransmitter

NeurofibrilLM: thread-liked dark brown networkEM: microfilament,neurofilament, neurotubuleFunction: cytoskeleton, participate in substance transport

Neurofibrils

Nerve tissue

Hui Zhao

2. Process

Dendriticspine

Spinal apparatus

Dendrite

AxonAxon hillock, axon terminalAxolemma, axoplasmNo Nissl body and Golgi complexFunction: passes messages away from the cell body to other neurons, muscles, or glands)

DendriteDendritic spineSpine apparatusFunction: receive stimulation and conduct impulse into soma

Nerve tissue

Hui Zhao

2. Process

Axonal transportAnterograde axonal transport• Fast transport• Slow transport

Retrograde axonal transport

Nerve tissue

Hui Zhao

Classification of neurons

According to number of processesmultipolar; bipolar; pseudounipolar neuron

Nerve tissue

Hui Zhao

Classification of neurons

According to functions sensory neuron; motor neuron; interneuron

Nerve tissue

Hui Zhao

Classification of neurons

According to neurotransmitter Cholinergic neurons胆碱能神经元

Aminergic neurons 胺能神经元

Amino acidergic neurons 氨基酸能神经元

Peptidergic neurons 肽能神经元

Nerve tissue

Hui Zhao

Contents

NeuronNeuron1

SynapseSynapse2

NeurogliaNeuroglia3

Nerve Fiber and NerveNerve Fiber and Nerve4

Nerve EndingNerve Ending5

Nerve tissue

Hui Zhao

ClassificationChemical synapseElectrical synapse

A specialized junctions between neurons or neuron and non-nerve cells

II Synapse

Axon terminal

synaptic buttons

Dendriticspine

Spinal apparatus

Dendrite

Nerve tissue

Hui Zhao

Chemical synapse

LMSynaptic corpuscle or synaptic button

synaptic button

Nerve tissue

Hui Zhao

Chemical synapse

EM: Presynaptic element: presynaptic membrane, synaptic vesiclesSynaptic cleft Postsynaptic element: postsynaptic membrane

presynapticmembranesynaptic cleft

postsynaptic membrane

synapse vesicle

Nerve tissue

Hui Zhao

Classification of Chemical synapse

1

Axodendritic synapseAxospinous synapseAxosomatic synapseAxoaxonal synapseDendrodendritic synapse

2Type I synapseType II synapse

3Excitatory synapseInhibitory synapse

Nerve tissue

Hui Zhao

Synapse, EM.

synaptic vesicle

presynaptic membranesynaptic cleftpostsynaptic membrane

axonal terminal

Synapse

Nerve tissue

Hui Zhao

Synapse

Nerve tissue

Hui Zhao

Contents

NeuronNeuron1

SynapseSynapse2

NeurogliaNeuroglia3

Nerve Fiber and NerveNerve Fiber and Nerve4

Nerve EndingNerve Ending5

Nerve tissue

Hui Zhao

III. Neuroglia

1. Central nervous system : AstrocyteOligodendrocyteMicrogliaEpendymal cell

2. Peripheral nervous system: Schwann cell (Neurolemmal cell) satellite cell (capsular cell)

3. Functions support, nourish, protect, insulate , repairregulate the environment and movement of neuronsecret neurotrophic factor

Nerve tissue

Hui Zhao

Astrocytes

Astrocyte

Capillary

Neuroglial filament

End foot

Nerve tissue

Hui Zhao

Astrocytes

ClassifictionProtoplasmic astrocyteFibrous astrocytes Functions:

Form blood-brain barrierProduce the neurotrophic

factors (NGF)Repair never tissue

Nerve tissue

Hui Zhao

Blood-brain barrier (BBB)

Structure component Continuous endothelium of capillary Tight junctions between endothelial cellsContinuous basal membrane around endotheliumThe end feet of astrocytessurrounding the capillary

Function Prevent the passage of certain substances from the blood to nerve tissue(P111)

Nerve tissue

Hui Zhao

Oligodendrocyte

Function Forming myelin sheath of nerve fibers in CNSNourishment, protection.

Nerve tissue

Hui Zhao

Microglia

FunctionAmoeboid movement , phagocytosis.Stem cell, differentiation.

Microglia

Nerve tissue

Hui Zhao

Ependymal cell

Simple cuboidal or columnar epithiliumMicrovilli or ciliaFunction

Produce cerebrospinal fluidNourish and protect neuron

Ependymal cells

Nerve tissue

Hui Zhao

III. Neuroglia

1. Central nervous system : AstrocyteOligodendrocyteMicrogliaEpendymal cell

2. Peripheral nervous system: Schwann cell (Neurolemmal cell) Satellite cell (capsular cell)

3. Functions supporting, insulating , repairingregulate the environment and movement of neuronsecret neurotrophic factor

Nerve tissue

Hui Zhao

Schwann cell (Neurolemmal cell)

FunctionForming myelin sheath of nerve fibers in PNSRepair never tissueProducing NGF

Nerve tissue

Hui Zhao

Satellite cell (capsular cell)

Surrounding the neuron in ganglionFunction: protect and support neuron

Satellite cells

Nerve tissue

Hui Zhao

Contents

NeuronNeuron1

SynapseSynapse2

NeurogliaNeuroglia3

Nerve Fiber and NerveNerve Fiber and Nerve4

Nerve EndingNerve Ending5

Nerve tissue

Hui Zhao

IV Nerve Fiber and Nerve

Definition: Nerve fiber: axon enveloped by neuroglial cells

Classification: Myelinated nerve fiber

• Peripheral nervous system • Central nervous system

Unmyelinated nerve fiber

Nerve tissue

Hui Zhao

Myelinated nerve fibers of PNS

Myelin-sheathRanvier nodesInternode

Ranvier node Ranvier node

Nucleus of Schwann cell

Myelin-sheath

Internode

Nerve tissue

Hui Zhao

Myelinated nerve fibers of PNS

Schmidt-Lantermann incisureNeurokeratin networkNeurilemma

Nerve tissue

Hui Zhao

Myelinated nerve fibers of PNS

Nucleus of Schwann cell

Ranvier node

axon

Nucleus of fibroblast

Myelinesheath

Nerve tissue

Hui Zhao

Myelinated nerve fibers of PNS

axon

Myeline sheath

cytoplasmof Schwann cell

Nucleus of Schwann cell

unmyelinated fiber

Nerve tissue

Hui Zhao

Myelinated nerve fibers of PNS

Ranvier Node

S-L Incisure

S-L Incisure

Nerve tissue

Hui Zhao

Myelinated nerve fibers of PNS

axon

Nerve tissue

Hui Zhao

Myelinated nerve fibers of PNS

Myelinesheath

microtubuleNeurofilament

cytoplasmaof Schwann cell

axon

cytoplasmaof Schwann cell

Nerve tissue

Hui Zhao

IV Nerve Fiber and Nerve

Definition: Nerve fiber: axon enveloped by neuroglial cells

Classification: Myelinated nerve fiber

• Peripheral nervous system • Central nervous system

Unmyelinated nerve fiber

Nerve tissue

Hui Zhao

Myelin sheaths Processes of oligodendrocytesRanvier node are broadS-L incisure are absent.

Myelinated nerve fibers of CNS

oligodendrocyte

axon

Myelinesheath

process

Nerve tissue

Hui Zhao

Myelinated nerve fiber

Functions of myelin sheathProvide an insulation layer around the axon and to speed up impulse conductionNerve impulses jump from node to node across internodes of myelin sheath.

Nerve tissue

Hui Zhao

IV Nerve Fiber and Nerve

Definition: Nerve fiber: axon enveloped by neuroglial cells

Classification: Myelinated nerve fiber

• Peripheral nervous system • Central nervous system

Unmyelinated nerve fiber

Nerve tissue

Hui Zhao

Unmyelinated nerve fiber

Schwann cellsNo Ranvier nodeNo myelin sheath

axons

Schwann cell

Nerve tissue

Hui Zhao

4.3 Nerves

structure: epineurium: nerve perineurium: nerve fibers bundle endoneurium: nerve fiber

Nerve tissue

Hui Zhao

epineurium

perineurium

bundle

Nerves

Nerve tissue

Hui Zhao

Nerves

Nerve tissue

Hui Zhao

Contents

NeuronNeuron1

SynapseSynapse2

NeurogliaNeuroglia3

Nerve Fiber and NerveNerve Fiber and Nerve4

Nerve EndingNerve Ending5

Nerve tissue

Hui Zhao

5 Nerve Ending

5.1 Sensory or Afferent nerve endings

Receive physical and chemical stimuliGenerate nerve impulses responding to sitmuli5.1.1 Free nerve ending5.1.2 Encapsulated nerve endings

5.2 Motor or Efferent nerve endings Control the activity of muscle and gland5.2.1 Motor end plate5.2.2 Visceral motor nerve endings

Nerve tissue

Hui Zhao

5.1.1 Free nerve ending

epitheliumfree nerve endings

Nerve tissue

Hui Zhao

5.1.2 Encapsulated nerve endings

Connective capsule surround unmyelinated sensory nerve endings

Tactile corpuscleLamellar corpuscleMuscle spindle

Nerve tissue

Hui Zhao

Tactile corpuscle (Meissner corpuscle)

Dermal papillae

Tactile corpuscles

Epidermis

Dermal papillae

Epidermis

Tactile corpusclesNerve endings

Nerve tissue

Hui Zhao

Lamellar corpuscle (Pacinian corpuscle)

Hypodermis

Capsule

Flattened cell

Inner bulb1~ 4 mm

Capsule

Falttened cells

Inner bulb

Nerve tissue

Hui Zhao

Muscle spindle

Sensory nerve fiber ending

Motor nerve fiber ending

Motor end plate

Extrafusal muscle fibers

Nerve tissue

Hui Zhao

Muscle spindle

Muscle spindle, cross section Sensory nerve fiber ending

Muscle spindle, longitudinal section

Nerve tissue

Hui Zhao

5 Nerve Ending

5.1 Sensory or Afferent nerve endings

Receive physical and chemical stimuli, Generate nerve impulses responding to sitmuli5.1.1 Free nerve ending5.1.2 Encapsulated nerve endings

5.2 Motor or Efferent nerve endingsControl the activity of muscle and gland5.2.1 Motor end plate5.2.2 Visceral motor nerve endings

Nerve tissue

Hui Zhao

Motor end plate

motor nerve fiber endingmotor end plate

Nerve tissue

Hui Zhao

axon

Axon terminal

Schwann cell Synaptic vesicles contain acetylcholine

Basement membrane

Skeletal muscle cell

primary synaptic cleftmitochondria secondary

synaptic cleftsarcolemma

Motor end plate

Nerve tissue

Hui Zhao

Axon termianl with synaptic vesicles

Secondary synaptic cleft

sarcolemma

primary synaptic cleft

sarcolemma

Motor end plate

Nerve tissue

Hui Zhao

Motor end plate

Motor end plateSkeletal muscle

Motor nerve ending

Capillary

Skeletal muscle

Primary synaptic cleft

Motor end plate

Nerve tissue

Hui Zhao

Axon hillock

Motor end plate

Nerve tissue

Hui Zhao

Visceral motor nerve ending

Axon

Mitochondria

Varicosity

Target cell

PresynapticmembraneReceptor

Neurotransmitter

Synaptic cleftSynaptic vesicles

Postsynaptic membrane

Nerve tissue

Hui Zhao

Summary

Nerve tissue

Hui Zhao

Discussion Class

Group1：神经干细胞

Group2：造血干细胞

Group3：胚胎干细胞

Group4：肿瘤干细胞