U3 KA4b - Neurotransmitters Flashcards
What are Endorphins?
Neurotransmitters that stimulate neurones involved in reducing the intensity of pain
Increased levels of Endorphins are connected to…
euphoric feelings, appetite modulation and release of sex hormones.
Endorphin production increases in response to:
- Severe injury (promote pain-relief)
- prolonged and continuous exercise (promote pain-relief and boost moods)
- stress (in an attempt to counter-act stress response)
- Laughing (boost moods)
What is Dopamine?
A neurotransmitter which induces the feeling of pleasure and reinforces particular behaviours by activating the reward pathway in the brain
What are Neurotransmitter disorders usually linked to?
An imbalance in neurotransmitter release
Examples of Neurotransmitter disorders
- Alzheimer’s disease
- Parkinson’s disease
- Schizophrenia
- Depression
Name the 3 ways a drug can act to treat neurotransmitter disordered
- Some mimic the action of the neurotransmitter (agonist)
- Some may block the receptor preventing the action of the neurotransmitter (antagonist)
- Some inhibit the removal of the neurotransmitter from the synaptic cleft (inhibitors)
Describe Agonist Drugs
Agonists bind to and stimulate receptors mimicking the neurotransmitter and triggering a normal cellular response.
This means nerve impulses are transmitted, sometimes at an enhanced level
Describe Antagonist Drugs
Antagonists bind to specific receptors blocking the action of the neurotransmitter on the postsynaptic neuron.
Therefore normal transmission of nerve impulses is greatly reduced or stopped
Describe Inhibitory Drugs
Inhibitors prevent the removal of the neurotransmitter from the synaptic cleft
Some inhibitor drugs work by inhibiting the enzyme responsible for the degradation of the neurotransmitter (e.g. acetylcholine)
Others act by inhibiting the re-absorption of the neurotransmitter (e.g. noradrenaline) into the presynaptic neurons
Where do many recreational drugs affect neurotransmission?
In the reward circuit of the brain.
recreational drugs can cause changes in neurochemistry. What does this lead to?
- changes in mood (happiness, confidence, aggression)
- cognition (impairs problem solving and decision making)
- perception (Misinterpret stimuli- sounds, colours, sense of time)
- behaviour (sleep patterns, self-importance)
How do Recreational drugs work?
By mimicking or interacting with neurotransmitters in different ways
What are some of the things recreational drugs can do?
- stimulate the release of neurotransmitters
- Act as an agonist (mimic neurotransmitter action)
- Act as an antagonist (block neurotransmitter binding to receptors)
- inhibit their re-uptake
- inhibit their breakdown by enzymes
How does Drug Desensitisationwork?
Repeated use of a drug that acts as an agonist results in neurotransmitters being repeatedly stimulated and causes increased feelings of wellbeing and euphoria
The nervous system compensates for overstimulation of these receptors by reducing the number of receptors and reducing the sensitivity to the agonist drug
