1. Mood Disorders
Lesson 24

2. Mood Disorders Unipolar depression Mania Bipolar disorder
Seasonal Affective Disorder (SAD) ~

3. Unipolar Depression 2:1 females ~ Extreme sadness & despair
extent & duration important
Prevalence
females 9-26%
males 5-12%
2:1 females ~

4. Unipolar Depression endogenous vs. reactive Genetic component
DZ twins  25% concordance
MZ twins  70% concordance

5. Diagnosis & Symptoms Disrupted eating & sleeping
increased or decreased
Impaired concentration
Changes in activity
Feelings of guilt / worthlessness
Preoccupation w/ death or suicide ~

6. Diagnosis & Symptoms NOT uncomplicated bereavement organic Diagnosis
5 of 9 symptoms
not complete list
duration > 2 weeks ~

7. Treatment Psychotherapy Drug Therapy Electroconvulsive-shock Therapy
Sleep Deprivation
Light Therapy ~

8. Etiology Catecholamine hypothesis DA & NE deficiency
Evidence from drug side effects
Produce depression
reserpine – monoamines
propranalol - NE antagonist ~

9. Monoamine Hypothesis Fluoxetine (Prozac) therapeutic effects
blocks 5-HT reuptake
5-HT modulates other NTs?
usually more than one NT involved ~

10. Drug Treatment Monoamine oxidase inhibitors – MAOIs NT not degraded
more NT in synapse
Cheese effect
foods with tyramine
metabolism  amphetamine-like
risk of cerebral hemorrhage ~

11. Tricyclic Antidepressants
Indirect agonists
block monoamine reuptake
imipramine, desipramine
Side effects
Sympathetic arousal
Possible overdose ~

12. SSRIs Selective serotonin reuptake inhibitors Prozac (fluoxetine)
Zoloft (sertraline)
Paxil (paroxetine)
Luvox (fluvoxamine)
blocks 5-HT reuptake
Less effect on NE & DA ~

13. SSRIs vs Tricyclics Fewer side effects less danger of overdose
As effective as tricyclics
Neither addictive
Animals don’t self-administer
negative reinforcement ~

14. Criticisms Immediate effects on NT level
Therapeutic effects  2-4 weeks
Explanation?
Compensatory responses
Autoreceptor desensitization ~

15. Tetracyclic Antidepressants
Block reuptake & autoreceptors
Faster therapeutic effects?
yes...
but still a delay ~

16. Other Selective Reuptake Inhibitors
Norepinephrine Dopamine Reuptake Inhibitor (NDRI)
bupropion (Welbutrin)
Also tx bipolar & Smoking cessation (Zyban)
Side fx
less sexual dysfuntion than SSRI
Insomnia
seizures mg/dose limit
no subjective euphoria, abuse ~

17. Other Selective Reuptake Inhibitors
Selective Serotonin Norepinephrine Reuptake Inhibitor (SNRI)
venlafaxine (Effexor)
Serotonin-2 Antagonists/Reuptake Inhibitors (SARI)
Trazodone (Desyrel)
5HT2 –R: autoreceptor
Anxiety disorders, bulimia
Off-label use of antidepressants
wide variety of disorders ~

18. Electroconvulsive Therapy - ECT
Rapid effects - few days
Indications
drug therapy ineffective
danger of suicide
Risk of drug interactions
Mechanisms unknown ~

19. Sleep Deprivation Depression  Early & frequent REM
Tricyclics inhibit REM
REM deprivation
gradual therapeutic effects
Total sleep deprivation
immediate therapeutic effects
Mechanisms unknown ~

20. Mania & Bipolar Mania Symptoms Euphoria grandiose plans
reduced need for sleep
high risk activities
Bipolar Disorder
Cycling between mania & depression ~

21. Etiology Induced by drugs Monoamine agonists
cocaine, amphetamine, antidepressants
Mostly NE & DA ~

22. Treatment: Mania & Bipolar
Lithium most common
Dangerous, but thresholds well known
Mechanism unknown
affects almost all NTs
Also
Anticonvulsants
atypical neuroleptics ~