1. Mood Disorders Lesson 25

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

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

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

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

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

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

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

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

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

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

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

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

14. Criticisms n Immediate effects on NT level n Therapeutic effects  2-4 weeks n Explanation? l Compensatory responses l Autoreceptor desensitization n Tetracyclic Antidepressants l Block reuptake & autoreceptors l Faster therapeutic effects l but still a delay ~

15. Other Selective Reuptake Inhibitors n Norepinephrine Dopamine Reuptake Inhibitor (NDRI) l bupropion (Welbutrin) l Also tx bipolar & Smoking cessation (Zyban) n Selective Serotonin Norepinephrine Reuptake Inhibitor (SNRI) n Serotonin-2 Antagonists/Reuptake Inhibitors (SARI) n Off-label use of antidepressants l wide variety of disorders ~

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

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

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