Antidepressants Flashcards
What is unipolar depression?
Mood swings are always in the same direction, low mood, anhedonia, negative thoughts, pessimism, apathy.
This can all be accompanied by extreme changes in weight, low self esteem etc.
What are the causes of unipolar depression?
Some genetic components.
As a result of a situation or event that has caused the symptoms of the disease.
What is bipolar disease.
Depression alternates with mania, characterized by excessive exuberance, enthusiasm, self-confidence which may be combined with irritability, impatience and aggression etc.
When do we use medical intervention for depression?
When the symptoms mean that the patients are disrupted from their normal, everyday life.
What brain regions are implicated in depression?
Singulet nucleus.
Limbic system- ventral tegmental region which is involved in the reward pathway
Amygdala- hyperfunction in patients. Involved in fear response
Hippocampus- loss of BDNF in depressed patients due to cortisol
What are the supposed genetic factors of depression?
Postnatal depression- brainwaves from the mother can be transferred to the baby and they are at more risk of depression when they are older- epigenetic changes in the baby.
How to make an animal depressed?
Cause them stress- prolonged stress will cause the brain to respond in a depressed like way.
What are the cruel tests that people put animals through?
Forced swim test- given antidepressants which interfere with monoamine NT systems- animals continue to swim whereas depressed animals give up trying.
Tail suspension.
Alternating stressful situations e.g. put them in a confined space foe a day then make them swim etc- unpredictable stress.
What are the causes of depression?
Little evidence of substantial brain pathology.
Disturbance of hormone levels- high cortisol.
Lack of monoamine NT action (drugs which stop their metabolism alleviate symptoms). 5HT and NorA deficits can cause depressive symptoms.
How long do antidepressants usually take to have effect?
Weeks- there are long term trophic effects which need to occur, so even though the initial level of the NTs are increased- effects take longer to appear.
This suggests that the receptor and the NT can affect each others transcription.
What monoamine NT can have an effect on BDNF signalling
Seratonin
What evidence is there to support the monoamine hypothesis?
MAO inhibitors can alleviate symptoms.
Many antidepressant drugs were found to increase the amount of monoamines in the cleft.
What are the three main classes of antidepressants?
Monoamine oxidase inhibitors (MAO)
Tricyclic antidepressants
SSRIs
How do MAO inhibitors work?
MAO is found in and outside of the neuron
Cause a build up of amines in the synaptic terminal.
Two types- A which is used in the CNS and B in the PNS
