Antipsychotics

Question 1

Give 3 examples of positive and negative symptoms associated with schizophrenia

Answer 1

Negative:
-anhedonia 
-blunting of emotions
-withdrawal from social contacts
Positive:
-voices, delusions
-irrational and wild behaviour 
-delusions of grandeur

Question 2

What is the association between NMDA receptors and schizophrenia

Answer 2

NMDA antagonists (ketamine etc) produce positive and negative psychotic symptoms- Glu signalling is involved

Question 3

What is the association between 5-HT2A receptors and schizophrenia

Answer 3

5-HT2A agonists (LSD) produce psychotic symptoms

Question 4

What are 4 dopaminergic pathways in the CNS

Answer 4

1. Nigrostriatal
2. Mesocortical and mesolimbic
3. Tuberhypophyseal
4. Medullary chemoreceptor trigger zone

Question 5

How do amphetamines and cocaine increase dopamine levels?

Answer 5

1. By inhibiting MAO
2. By displacing DA (and NA) out of vesicles
3. Reversing the action of re-uptake transporters

Question 6

What 2 things do amphetamines and cocaine cause?

Answer 6

1. Activation of reward pathways

2. Increased motor activity

Question 7

Example of a class of antipsychotic drugs and their main side effects

Answer 7

Phenothiazines- e.g chlorpromazine
D2 antagonists
side fx= motor disturbances (extrapyramidal) and muscular twitches

Question 8

Examples of new drugs with fewer side fx

Answer 8

Sulpiride and clozapine