Chapter1 Single

8/14/2019 Chapter1 Single

1/21

Functional Neuroanatomy

Mazyar Fallah

8/14/2019 Chapter1 Single

2/21

Course Website

www.yorku.ca/mfallah/kine3650

8/14/2019 Chapter1 Single

3/21

Neurohistology

Characteristics of cells of the nervous

system Two main types of cells:

Neurons Glia, from Greek for glue.

Support neurons.

8/14/2019 Chapter1 Single

4/21

8/14/2019 Chapter1 Single

5/21

General Neuron Anatomy

Dendritic Tree

Cell Body

Nucleus

Axon

Axon Hillock

PresynapticMembrane

Bipolar Neuron

8/14/2019 Chapter1 Single

6/21

Cell Body Organelles

8/14/2019 Chapter1 Single

7/21

Myelin

Insulation

Covers axons Nodes of Ranvier

Schwann cell PNS Oligodendrocyte -

CNS

8/14/2019 Chapter1 Single

8/21

Dendrites

Increase the receptive

surface area Spines

Receive synaptic contactfrom other neurons

Can be quite complicated

8/14/2019 Chapter1 Single

9/21

8/14/2019 Chapter1 Single

10/21

Glial Cells

Ependymal cells

Spinal cord Ventricles

Producecerebrospinal fluid(CSF)

8/14/2019 Chapter1 Single

11/21

Nerve Fibers

Peripheral nerves

Vary in diameter

Myelinated or not

Sensory, Motor, or Both

8/14/2019 Chapter1 Single

12/21

Peripheral Nerve Connective

Tissue Epineurium surface

Thick, protective, shockabsorber

Perineurium

surrounding Partitions groups of nerve

fibers

Endoneurium interior Covers each axon, contains

Schwann cells.

8/14/2019 Chapter1 Single

13/21

Axonal Transport

Anterograde

Get materials to axonterminal

Slow or Fast

Retrograde Return materials to cell

body

Recycling system

Microtubules and kinesin

Highways and trucks

8/14/2019 Chapter1 Single

14/21

Synapses

Excitatory vs Inhibitory

Electrical vs Chemical

8/14/2019 Chapter1 Single

15/21

Neuromuscular Junction

Axon synapses on

muscle fiber Acetylcholine (ACh)

neurotransmitter Motor end plate

8/14/2019 Chapter1 Single

16/21

AP

Ca2+entry

Ca2+

ACh release

Muscle

contraction

AChE

Na+

ACh- esterase

AChE breaks down ACh in the synaptic cleft

Poisons Acting

8/14/2019 Chapter1 Single

17/21

Botulism

Poisons Acting

At NMJ(affecting ACh)

curare

nerve gase.g. sarin

Source: Haines, Fundamental Neuroscience, Churchill-Livingstone, 2002

8/14/2019 Chapter1 Single

18/21

Source: Purves et al. Neuroscience, Sinauer Associates Inc: Massachusetts, 2001.

Neurotoxins

Krait snake

blocks receptors at NMJCone shell snail

Block postsynaptic receptors,

postsynaptic channels,presynaptic release of ACh

M h i G i

8/14/2019 Chapter1 Single

19/21

Myasthenia Gravis

Source: Kandel et al., Principles of Neural Science, McGraw Hill, 2000

Normal Myasthenia gravisaxon

Musclefibre

Junctionalfolds

Axonterminal

ACh

receptors

Synaptic

vesicle

8/14/2019 Chapter1 Single

20/21

Source: Kandel et al., Principles of Neural Science, McGraw Hill, 2000

Myasthenia Gravis Treatments

One minute afterAChE Inhib.

Patient with MG

8/14/2019 Chapter1 Single

21/21

Neuronal Injury

Crushing vs Severed Chromatolysis

changing fromproducing NTs toproducing materials

for repair Retrograde vs

Anterograde

degeneration Walleriandegeneration