5HT And NE Flashcards
What are the two types of monoamines?
Indolamines and catecholamines
Out of dopamine, norepinephrine, epinephrine, and serotonin, which of the above are indolamines?
Serotonin
What is the rate limiting enzyme on the path from L-tyrosine to Epinephrine?
Tyrosine hydroxylase (TH)
What are the enzymes that inactivate catecholamines?
MAO and COMT
What is MAO-A selective for?
NE and serotonin
What is MAO-B for?
It acts on dopamine and broad spectrum of phenylethylamines
Norepinephrine deficiency syndrome common symptoms:
- impaired attention
- depressed mood
- psychomotor retrardation
Serotonin containing neuronal cell bodies are mainly restricted to discrete clusters of cells located along the midline of the brain stem - _________
The raphe nuclei
5-HT 1A is located where? what does it cause?
Somatodendritic auto receptors and postsynaptic ; decrease in firing and decrease in 5HT release
5-HT 1D is located where? What does it do?
Terminal auto receptors ; inhibit release of neurotransmitters
What are the serotonin receptors for mood?
Postsynaptic beta 1 receptor
What is the function of 5HT 2A?
- stimulation of phospholipase C
- closing of K+ channels
What serotonin receptors are involved in anxiety and panic?
5HT-2A and 5HT-2C
What serotonin receptors are involved in appetite and eating behavior?
5HT-3
What serotonin receptors are involved in appetite and GI motility?
5HT-3 and 5HT-4
What serotonin receptor is involved in sleep?
5HT-2A
What serotonin receptor is involved in the vomit center?
5HT-3
What are the symptoms of serotonin deficiency syndrome?
- depressed mood
- anxiety
- panic
-phobia - anxiety
- obsessions and compulsions
- food craving; bulimia
What happens when the alpha 2 hetero receptor is activated on the serotonin neuron?
It inhibits 5HT and NE
What is the alpha 1 receptor coupled to?
Gq
Alpha 1 ______ 5HT production while alpha 2 ______ it
Increases; inhibits
What was the original purpose for MAO inhibitors?
To treat tuberculosis
What was the first drug discovered to treat depression?
MAO inhibitors
the original MAO inhibitors were __________ and ___________
Non-selective and irreversible
What kind of MAO inhibitors are irreversible and nonselective?
Classical MAO inhibitors
What are RIMAs?
Reversible inhibitors of MAO A (and they aren’t very effective)
True or False: selective inhibitors of MAO B are used for depression
False
What happens to the level of dopamine when MAO-B is inhibited?
It is elevated
Increased MAO-___ is thought to be linked with some types of treatment-resistant depression and vulnerability to relapse
A
What kind of MAO inhibitors do you use to treat treatment-resistant depression?
MAO-A
What were tricyclic antidepressants originally used to try to treat?
Psychosis
What does NRI stand for?
Norepinephrine reuptake inhibition
what is the tricyclic antidepressant M1 receptor associated with?
Dry mouth drowsiness
What is the H1 receptor associated with?
Weight gain
What is the tricyclic alpha receptor associated with?
Dizziness and decreased blood pressure
What are the two reasons why SSRIs work differently between people?
- pharmacodynamics
- pharmacokinetics
Fluoxetine is a 5HT2C ________ that causes release of NE and DA
Antagonist
Monoamine hypothesis
The reason why have depression is because we have a lack of monoamines. If we were to raise the monoamine levels, depression would be cured.
Is the monoamine hypothesis accurate?
No it is an incorrect theory
In the raphe nucleus, the increase of 5-HT causes a ______________ of the auoreceptors. This releases the inhibition on serotonin release in the terminals.
Down-regulation
what happens when there is an increase of 5-HT at the terminals?
Effect on mood. This will case down-regulation of the postsynaptic receptors
