Neurotransmitters and Receptors Flashcards
How quickly do neurotransmitters act and why?
Act very quickly by producing fast EPSPs and IPSPs
How fast are the EPSPs and IPSPs produced by neurotransmitters?
Very fast - milliseconds
How quickly do neuromodulators act and what do they act through?
Act slowly through GPCRs
How fast are the EPSPs and IPSPs produced by neuromodulators?
Very slow that last for several hundred millseconds
What two groups can classical neurotransmitters be divided into?
- Excitatory transmitters
2. Inhibitory transmitters
What is an example of an excitatory neurotransmitter?
L-glutamate
What is an example of an inhibitory neurotransmitter?
GABA
What two groups can neuromodulators be divided into?
- Monoamines
2. Neuropeptides
What are three examples of monoamines?
Noradrenaline, dopamine and serotonin
What are two examples of neuropeptides?
Substance P and Enkephalin
What are the criteria that must be satisfied in order to classify something as a neurotransmitter?
- It must be synthesised in the presynaptic neuron
- It must be stored in the presynaptic neuron (high concentrations must be present in the axon terminal)
- It must be be released from the presynaptic terminal
- It must diffuse across the synaptic cleft
- It must have an action of the postynaptic membrane
- It must be inactivated
Where are neurotransmitters stored in the presynaptic membrane?
In vesicles
Where does neurotransmitter synthesis take place?
The the axon terminal/presynaptic element
What is the precursor for acetylcholine and what is the enzyme that converts it to Ach in the axon terminal?
Choline and acetic acid (acetyl coA) are converted to acetylcholine by choline acteyl transferase
Where are neuropeptides synthesised?
In the cell body