Wk 9.1 Depression and Anxiety Flashcards
What is the most common psychiatric disorder and what genetic component is most likely to obtain it?
Depression
Concordance ratefor monozygotic twins with bipolar may reach 80%
What are the two types of Depression?
Unipolar- major depression
Bipolar- Episodes of mania
What are the subtypes of unipolar depression and what symptoms do they show?
-Melancholic depression=Depression with diurnal variations in mood, Insomnia, Anorexia, Loss of interest and Loss of capacity for joy
-Atypical depression= Depression with diurnal variations in mood, Weight gain, Anxiety and Loss of interest in activities but cheer up temporarily when good things happen
What are the symptoms of Bipolar depression?
-Alternating euphoria and depression
-Depression similar to that of unipolar type
- Manic episodes: elevated, expansive mood over-talkativeness,increased energy and libido, decreased need for sleep. Can also include hallucinations and delusions.
What are the two types of bipolar and what is the difference between them?
Type I: at least 1 full manic episode and atleast 1 episode of major depression
Type II: at least 1 episode of hypomania and1 episode of major depression
What cause disruptions?
- Monoamine hypothesis= dopamine, 5HT,NA and A
- Neurotrophic hypothesis of depression= BDNF-1, NP,NM,Growth factors
What is the Evidence of brain regions involved in mood disorders?
-Enlargement of amygdala
- Hippocampal atrophy in depression-correlated to amount and duration of priorepisodes of depression
-Feedback mechanisms within HPA axis areimpaired – lack of inhibition of cortisol
How does MAOI work?
-Dopamine is released to the synaptic cleft and gets reuptake, and by specific dopamine transporters
-The presynpatic terminal converts into 3-4 dihydroxyphenyl acetic acid and it metabolised
- MAOI inhibits MAO which is used for the conversion of dopamine to other intermediates making it more persisant
- Dopamine is reuptaked to the presynaptic cleft and is degraded by 1. MAO coverting D=-4 dihydroxyphenyl acetic acid and 2. Catechol-O-methyl transferase converting D= 3 methyoxytryamine
What do both intermediated get coverted to in the end?
Hamolalignic acid
what is the Evidence of monoamine disruption?
Reserpine- used to treat Hypertension and mental disorders
- Induces depression
-Produced depression-like syndrome,motor retardation and sedation in animals
-Thought to inhibit vesicular storage of severalneurotransmitters (mainly 5HT and NE)
What is the production of serotonin?
-Tryptophan–tryptophan hydroxylase= 5-Hydroxy-Tryptophan
-Hydroxy-Tryptophan–Aromatic amino acid decarboxylase= 5-Hydroxy-Tryptamine
What is the production noradrenaline?
-Tyrosine– Tyrosine hydroxylase= L-dopa
-L-Dopa– Aromatic amino acid decarboxylase= Dopamine
-Dopamine– Dopamine-β-hydroxylase= Noradrenaline
What does depression involve?
Depression involves a decrease in availability of monoamines
What does depression medication known as SSRI & SSNI stop?
Stops reuptake the the neurotransmitter allowing it to bind to the receptors on the post synpatic and increase monoamines in the synpatic cleft
What are environmental componenet of depression and what do they effect?
-Chronic stress, early-life experiences, lack of maternal care, physical abuse and parental violence
-Affect the resilience against adverse effects andincrease the likelihood to develop depression