Block 4 Lecture 6 -- Depression

Question 1

Define unipolar depression.

Answer 1

mental disorder;

• • pervasive and persistent low mood
• • low self esteem
• • loss of interest/self-pleasure

Question 2

What are the types of unipolar depression?

Answer 2

1) major depressive disorder
2) persistent depressive disorder
3) psychotic depression
4) postpartum depression
5) substance- or med-induced depressive disorder
6) PMDD
7) SAD

Question 3

What is persistent depressive disorder?

Answer 3

• • depressed mood ≥ 2 years

- - episodes of major depression w/ period of less severe sxs

Question 4

How effective is light therapy in SAD?

Answer 4

50%

Question 5

What populations are most likely to get depression?

Answer 5

1) females
2) indians, alaskans, whites, hispanics
3) prevalence decreases with age

Question 6

What are the categories of symptoms of depression?

Answer 6

1) psychological symptoms

2) somatic symptoms

Question 7

psychological symptoms of depression:

Answer 7

• • intense sadness, pessimistic worry, depressed mood, reduced self-esteem
• • loss of interest/enjoyment
• • suicidal thinking
• • impaired cognition, memory

Question 8

somatic symptoms of depression:

Answer 8

• • agitation
• • fatigue, loss of drive & libido
• • reduced appetite, weight change
• • bowel disturbances
• • motor retardation

Question 9

What are the theories for pathology in depression?

Answer 9

1) monoamine hypothesis

2) neurotrophic hypothesis

Question 10

What is the monoamine hypothesis?

Answer 10

1) deficiency in monoamine signaling: synthesis, storage, or release
2) deficiency in monoamine signaling due to receptor insensitivity

Question 11

What is the neurotrophic hypothesis?

Answer 11

BDNF is decreased in depression

– decreased neuronal plasticity (dendritic sprouts)

Question 12

What is the function of BDNF?

Answer 12

regulation of…

1) neuronal plasticity
2) growth
3) resilience
4) neurogenesis

Question 13

What is CREB?

Answer 13

cAMP response element binding protein

– yields BDNF

Question 14

What substances affect [CREB]?

Answer 14

increased by:

• • monoamines
• • Glu
• • BDNF

decreased by:
– glucocorticoids

Question 15

What is the DSM-5 criteria for diagnosis?

Answer 15

5+ symptoms for 2+ weeks

Question 16

How is mild-moderate depression treated?

Answer 16

CBT

Question 17

How is MDD treated?

Answer 17

CBT + other things

Question 18

What non-drug therapies are used for depression?

Answer 18

CBT

exercise, light therapy, group therapy, mediation/yoga

Question 19

Why is stress implicated in depression?

Answer 19

yields cortisol
– decreased CREB
yields Glu
– acts on NMDAr to result in neural apoptosis

Question 20

What are the strengths of the monoamine hypothesis re: receptor insensitivity?

Answer 20

1) chronic antidepressant administration causes change in expression/function of receptors
2) receptor plasticity correlates with time course of improvement

Question 21

What are the weaknesses of the monoamine hypothesis re: receptor insensitivity?

Answer 21

some drugs don’t work on the monoamine system

Question 22

What are the strengths of the monoamine hypothesis re: synthesis, storage, release?

Answer 22

1) reserpine led to depression
2) most antidepressants work on monoamines
3) studies show change in monoamine function
4) polymorphism in promoter of SERT in depression

Question 23

What are the weaknesses of the monoamine hypothesis re: synthesis, storage, release?

Answer 23

1) neurochemical effects in 1-2 days, but improvement takes 10-21 days
2) studies show normal monoamine levels in depression
3) some drugs don’t act on monoamines

Question 24

Describe effect of NE binding receptor in depression?

Answer 24

Gs

– increase CREB

Question 25

Describe the 5-HT receptor.

Answer 25

Gi

• • but, use PLC, IP3, PKC pathway
• • yields CREB

5-HT 1A and 1B are presynaptic

Question 26

Describe the NE receptors involved in monoamine antidepressant signaling.

Answer 26

Gs

– yield CREB

Question 27

What are the strengths of the neurotrophic hypothesis?

Answer 27

1) antidepressant increase neurogenesis and change synaptic connectivity
2) pain, stress = decreased BDNF
3) structural changes, loss of volume observed in hippocampus
4) BDNF = antidepressant-like effects in rodents
5) BDNF gene mutation = altered anxiety and depressive behavior in animals and humans

Question 28

Describe weaknesses of the neurotrophic hypothesis.

Answer 28

1) BDNF KO mice don’t exhibit depression/anxiety

2) increased [BDNF] in animals after social stress

Question 29

What are the effects of increasing NE, 5-HT, BDNF in depression?

Answer 29

1) decrease detrimental gene transcription
2) increase beneficial gene transcription
- - improve neurogenesis
- - inhibit apoptosis

Question 30

Depression is associated with:

Answer 30

1) shorter life expectancy
- - death 2x
- - suicide 26x
- - susceptibility to other infections
2) recurrence if sxs have not fully resolved (80% of MDD)