Depression Flashcards
What is unipolar depression?
When the mood change is only in one direction
What is bipolar depression?
When the mood can change drastically in multiple directions
Name four classes of anti-depressive drugs.
1) SSRI
2) Tricyclic AD
3) Monoamine oxidase inhibitors
4) 5-HT - NA reuptake inhibitor
What is the basis for the monoamine hypothesis?
Depletion of 5-HT and NA in the brain
(excess in mania)
How can reserpine stabilise mood?
It blocks the vesicular reuptake of 5-HT and NA
What is a monoamine oxidase?
An enzyme that catalyses the deamination of of 5-HT, NA and DA
What are the types of MAO and what do they act on?
MAO-A acts on DA and phenylethylamine
MAO-B acts on 5-HT, NA, DA and tyramine
How can an MAO inhibitor decrease depression symptoms?
Preventing the depletion of neurotransmitters, thus decreasing symptoms
What should people on MAOIs not eat?
High tyramine foods, such as cheese
What makes a drug a tricyclic antidepressant?
It has 3 benzene rings
Name a tricyclic AD
Imipramine
Does imipramine work for both mania and depression?
No, only for depression
How does imipramine cause its effects?
Primarily, it blocks uptake 1 but can cause side effects when it blocks uptake 2
What can happen when imipramine binds to H1 receptors?
A sedative effect
What happens when imipramine binds to α-1 and 2 receptors?
It induces postural hypertension
What happens when imipramine binds to mACh receptors?
It can cause a dry mouth, blurred vision and constipation
How do SSRIs exert their effects?
They block the reuptake channel of 5-HT
What are the classes of RIs?
1) 5-HT+NA RI
2) NA selective RI
3) NA+DA RI
How common is overdosing on SSRIs?
Infrequent as they are hard to overdose on
What are some common side effects of SSRIs?
GI issues and lowered libido
What is a potentially dangerous risk in children, when taking SSRIs?
Increased suicide risk
What is it called when excessive- but not fatal- overdoses of SSRIs are taken?
Serotonin syndrome
Which drugs can also block the reuptake of neurotransmitters?
Cocaine and amphetamine
Name 5 atypical antipsychotics
1) Trazodone
2) Mirtazapine
3) Mianserin
4) Bupropion
5) Venlafaxine
What are some characteristics of bupropion?
It is neither sedative nor euphoric.
It is a NDRI
It has DA<NA selectivity
What are some characteristics of venlafaxine?
It is an SNRI
It is fast acting
Why are St John’s Worts not good?
They are homeopathic and contain an unknown concentration of hyperforin, therefore can have side effects
Are there genetic factors involved with depression?
Yes, there is a ~37% inheritability, but there are no discernable treatments for this
Which receptors does mianserin antagonise?
α-1, α-2, 5-HT2a and H1
Which receptors does mirtazapine antagonise?
α-2, 5-HT 2c and 3
Also claimed to have fast onset
What class of drug, other than being atypical AP, is trazodone part of?
Noradrenergic and specific serotonergic antidepressant
Which receptors does trazodone block?
5-HT 2a and 2c and H1
Comment on trazodone as a reuptake blocker
It is a weak 5-HT reuptake blocker
Which neuroendocrine pathway is thought to be dysnfunctional in depression?
The hypothalamic-pituitary axis
Neurotrophy in which brain regions is associated with depression?
Neuronal loss in the hippocampus and prefrontal cortex
What can stress result in an increase of?
CRF, Cortisol and glutamate
How does an increase in CRF, cortisol and glutamate result in depressive symptoms?
Via a complex signalling pathway, it results in increased neural apoptosis and decreased neurogenesis
What are three promising future therapies for use in depression?
1) Circadian rhythm treatment with melatonin
2) Ketamine infusion
3) ECT/ TMS
Which drug classes can be useful in stabilising mood in bipolar?
Anti-epileptics, Atypical antipsychotics and lithium
How is lithium thought to help in bipolar disorder?
It interferes with a wide variety of signalling pathways that results in promoted inhibition and reduced excitation
Comment on the practicality of lithium as a mood stabiliser
It has a very narrow therapeutic window and it can be highly nephrotoxic
