Lecture 4: Neurotransmitters and Pharmacology Flashcards
What does information transfer across the synapse require?
Release of neurotransmitters and interaction with postsynaptic receptors
What are key features of synaptic transmission?
- rapid timescale
- diversity
- adaptability
- plasticity
- learning and memory
What do the spines on dendrites do?
Increase surface area for more synaptic connections
How does the way the information is being transferred change?
The transmission is electrical in the pre-synaptic neurone before becoming chemical neurotransmission when it passes across the synapse and then it returns to electrical transmission in the post-synaptic neurone
What are the 3 stages of synaptic transmission?
- Biosynthesis, packaging and release of neurotransmitter
- Receptor action
- Inactivation
What can neurotransmitters be?
- amino acids (e.g. glutamate, GABA)
- amines (noradrenaline, dopamine)
- neuropeptides (e.g. opioid peptides)
What is the most important excitatory neurotransmitter?
glutamate
What is the most important inhibitory neurotransmitter?
GABA
Which inhibitory neurotransmitter is present in the spinal cord?
glycine
What is considered a rapid effect or slower effect?
Rapid = us - ms slower = secs
What does neurotransmitter release rely on?
increase in intracellular Ca2+ (200um) - this occurs by opening of Ca2+ ion channels
What in the presynaptic neurone provides the source of neurotransmitter?
synaptic vesicles
Outline the steps that lead to neurotransmitter release.
- membrane depolarisation
- Ca2+ channels open
- Ca2+ influx
- Vesicle fusion
- Vesicle exocytosis
- Transmitter release
What is the process called from the Ca2+ channels opening to transmitter release?
Electrochemical transduction
What are the synaptic vesicles?
Vesicles docked in the synaptic zone filled with neurotransmitter
What are the proteins on synaptic vesicles called and what are they important for?
Vesicular proteins - important in docking/fusion process and exocytosis