01 CNS Cells

Gial Cells

• non neuron cells

Neurons

AP

• at rest: high Na concentration outside cell, K leak out constantly maintain -70

• depolarize: Na open, raise voltage. More channels open down the axon

• At end of cell, Ca channels open, NT released

• depolarization: Na in

• repolarization: K out

Astrocytes

• repair, scar, clean up NT

Microglia

• HIV hide in microglia

Oligodendroglia

• aka oligodendrocytes

Schwann

Myelin

• conduction velocity: speed at which electricity go down

• length constant: how far go down neuron until 1/3 left of original strength

Nerve Fibers

• small fibers easier blocked by Na blockers (no pain but still touch)

Sensory Nerves

Free Nerve

Meissner

• fingertips

Pacinian

Merkel

Peripheral Nerves

• Nerve trunk

• fasciculus: made up of small nerves

• endoneurium inflammed in GBS