Antipsychotics Flashcards
Where are amine transmitters localised to in the CNS?
Brain stem and basal forebrain
What are the brain stem and basal forebrain functions associated with?
“High level behaviours”, e.g emotion, cognition and awareness
What are noradrenaline α1 receptors associated with?
Motor control
Cognition
Fear
What are noradrenaline α2 receptors associated with?
Blood regulation
Sedation
Analgesia
Where are noradrenaline β1 receptors located and what effects do they have?
Cortex, striatum and hippocampus
Contributes to antidepressant long term effects
What does the locus caureleous control?
Controls wakefulness and alertness
Controls mood
What are mesolimbic and mesocortical pathways associated with?
Stereotypic behaviours
Increased mesolimbic- positive symptoms, D2 activity
Decreased mesocortical- negative symptoms
What is the nigrostriatal pathway associated with?
Fine motor control
What is the tuberohypophyseal pathway associated with?
Prolactin secretion from the pituitary
What enzymes are involed with breakdown of neurotransmitters?
MAO and COMT
Where are dopamine neurons lost in parkinsons disease
Nigrostriatal pathway
Substantia nigra
What dopamine receptors are found in the cortex?
Gs: D1 and D5
What dopamine receptors are found in the pituitary and DA neurons?
Gi: D2, D3 and D4
What do Gs dopamine receptors stimulate?
Adenylyl cyclase -> cAMP, PKA
What do Gi dopamine receptors stimulate?
Inhibit adenylyl cyclase
Activate potassium channels
Deactivate voltage gated calcium channels
Oppose D1 activation effects
What is the mechanism of amphetamines?
Displace DA and NA from vesicles, causing re-uptake
What are amphetamine-like drugs used to treat?
ADHD and narcolepsy
What is the mechanism of cocaine?
Inhibits DA transporters back into nerve terminals. This leads to an increase in motor activity
What are the positive symptoms of schizophrenia?
Hallucinations
Paranoia
Defective selective attention
Stereotypic activity
Aggression
(Hallucinations and craziness)
What are the negative symptoms of Schizophrenia?
Blunting of emotions
Withdrawal from social contacts
Reluctance to perform everyday tasks
What can cause schizophrenia?
Hereditary abnormalities arising in early life
Cannabis consumption in adolescence combined with genetic predisposition
What can be used to treat the positive symptoms of schizophenia?
D2 receptor antagonists
How do brains of schizophrenia patients compare to non schizophrenic brains?
Larger lateral ventricles
Less tissue ion the left temporal lobe
What sort of drug is LSD?
Serotonin receptor agonist
Outline the dopamine theory of schizophenia
- Amphetamines mimic behaviours similar to schizophrenia
- Hallucinations are a side effect
- D2 receptor agonists in animals produces stereotypic behaviours
- DA antagonists and DA vesicle disruptors control positive symptoms
What were the side effects of first generation antipsychotics?
Motor disturbances
Prolactin secretion
List some side effects of neuroleptics
Parkinson’s-like symptoms
Acute dystonias (muscle spasms) which slowly become irreversible
Increased prolactin release
Sedation
hypotension
Weight gain
