Chemical Synapses Flashcards
Chemical synapses are studied by…
- Neurobiologists
- Cell biologists
- Physiologists
- Geneticists
- Biochemists
- Psychologists
- Pathologists
Types of synapse…
- Axodendritic
- Axosomatic
- Axoaxonic
- Dendrodendritic
Synapses allow information processing that is…
- Complex
- Elaborate
- Subtle
- Flexible
What does defective neurotransmission cause?
Many neurological and psychiatric disorders
Neuromuscular junction structural features
- Pre and post synaptic membranes with a synaptic cleft in between
- Secretory granules containing neurotransmitter
- Receptors on post synaptic membrane responsible for binding chemical substances which transmit the signal from the presynaptic neuron
Synapses can be…
- Different sizes
- Can grow
- Can shrink
Larger synapses usually have ____ active zones
More
Synapses can release transmitter from ______ active zone in a terminal
More than one
Steps in transmission
- Synthesis
- Storage
- Release
- Postsynaptic effects
- Inactivation
Where are neuropeptides synthesised?
In the soma
Where are neuropeptides stored?
Secretory granules
Where are ACh, amines and amino acid neurotransmitters synthesised and packaged?
At the synaptic terminal
Where are ACh, amines and amino acid neurotransmitters stored?
In secretory vesicles
Why are some NT vesicles docked at terminal before an AP?
To allow rapid release
What does the arrival of an action potential do?
Opens voltage-gated Ca2+ channels
What does the opening of Ca2+ channels trigger?
Vesicle fusion and release - exocytosis
Main types of receptor
- Ligand-gated ion channels (ionotropic)
- G-protein coupled receptor (metabotropic)
Ionotropic channels
- Fast acting
- Open transiently in response to NT binding
Transmitter release at a ‘fast’ excitatory chemical synapse generates an…
Excitatory post-synaptic potential (EPSP)
Transmitter release at a fast inhibitory chemical synapse generates an…
Inhibitory post-synaptic potential (IPSP)
G-protein coupled receptors
- Synaptic transmission is slower and more complex
- Signal amplification
- May affect multiple channels
Many G protein coupled receptors act as….
Modulators
Termination of transmission
Occurs by
- Reuptake
- Diffusion
- Breakdown
