presynaptic axon terminal postsynaptic membrane terminal button dendritic spine

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Page 1: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine
Page 2: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

PresynapticAxon Terminal

PostsynapticMembrane

Terminal Button Dendritic

Spine

Page 3: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(1) Precursor Transport

Page 4: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

_ _ _

NT

(2) Synthesis

enzymes/cofactors

Page 5: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(3) Storage

in vesicles

Page 6: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Synapse

Vesicles

NT

Terminal Button

Dendritic Spine

Page 7: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Synapse

Terminal Button

Dendritic Spine

(4) Release

Receptors

Page 8: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Synapse

Terminal Button

Dendritic Spine

AP

Page 9: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Ca2+

Exocytosis

Page 10: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine
Page 11: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(5) Activation

Page 12: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Quantum releaseEach vesicle contains one quanta of

neurotransmitter (approximately 5000 molecules) – quanta release

Page 13: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(3) Transmitter Inactivation

1. Reuptake by presynaptic terminal2. Uptake by glial cells3. Enzymatic degradation4. Presynaptic receptor5. Diffusion6. Combination of above

Page 14: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(6) Termination

Page 15: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(1) Termination by... Diffusion

Page 16: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(2) Termination by...Enzymatic degradation

Page 17: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(3) Termination by...• Reuptake by presynaptic terminal• Uptake by glial cells

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(4) Termination by... Autoreceptors

A

Page 19: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

2. Receptor ActivationNS uses 40 families , act on 100 types of receptors; cause EPSPs and IPSPs,

Neuromodulators cause, via 2nd messengers, more complex metabolic effects in the PSM.

Ionotropic channel– directly controls channel– fast

• Metabotropic channel– second messenger systems– receptor indirectly controls channel ~

Page 20: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

(1) Ionotropic ChannelsneurotransmitterNTChannel

Page 21: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Ionotropic Channels

NT

Pore

Page 22: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Ionotropic Channels

NT

Page 23: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

Ionotropic Channels

NT

Page 24: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

G protein: Protein Phosphorylation

Receptor

trans-ducer

primaryeffector

external signal: nt

2d messenger

secondary effector

Receptor

trans-ducer

primaryeffector

external signal: NT

2d messenger

secondary effector

GS

norepinephrine

cAMP

protein kinase

b adrenergic -R

adenylylcyclase

Page 25: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

G protein: Protein Phosphorylation

RG

GDP

AC

PK

Page 26: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

G protein: Protein Phosphorylation

R

AC

PK

G

GTP

ATP

cAMP

Page 27: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine

G protein: Protein Phosphorylation

R

AC

PK

G

GTP

ATP

cAMP

P

Pore

Page 28: Presynaptic Axon Terminal Postsynaptic Membrane Terminal Button Dendritic Spine