I V I V The inferior olivary nucleus is the only source of cerebellar climbing fibers.

I

V

I

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The inferior olivary nucleus is the only source of cerebellar climbing fibers

The Inferior Olive nucleus

Olivary neurons (Ramon Y Cajal)

Intracellular labeling of olivary neuron HRP filled olivary neuron

Action potential in olivary neuron

Action potentials in olivary neuron

The effect of TTX on action potentials in olivary neuron

The effect of Mn2+ and Cd2+ on action potentials in olivary neuron

-68 mV

-60 mV

-60 mV

-55 mV

Two types of action potentials in olivary neuron

20 msec

1 nA

15 mV15 mV

-60 mV

The Na+ and Ca2+ components of the two types of action potentials

TTX

Independent activation of the action potentials

Refractory period of the action potentials

10 mV

Refractory period of the action potentials

The Inactivation curve of the low threshold action potential

Possible mechanism of rhythmic activity

Ionic currents in Olivary neurons:

Na current – typical H&H current

Dendritic Ca current – high threshold non-inactivating

Ca dependent, K current

Somatic Ca current – low threshold inactivating

Possible mechanism of rhythmic activity

Cell 1 Cell 2

Cell 1

Cell 2

10 mV5

200 ms

10 mV

20 mV

Cell 1

Cell 25 mV

200 ms

Cell 1

Cell 22 mV

100 ms

20 mV

Electrical coupling between olivary neuron

Dye coupling between olivary neuron

The olivary glumerulus

Olivary Gap junction