Schizophrenia 1 Flashcards
_% of the population are affected
1
give some of the general symptoms of schizophrenia spectrum problems
bizarre delusions inappropriate affect hallucinations paranoia incoherent thought odd behaviour
what are the 4 historical thought causes of schizophrenia?
- genetics
- environmental causes
- cannabis
- neurotransmitters (DA)
what is the concordance rate for identical monozygotic twins?
45%
what is the concordance rate for dizygotic twins?
10%
why must there be other factors than genes for schizophrenia?
because there is only a 45% concordance rate for identical twins so 55% must be due to other factors
what factors may cause schizophrenia?
- infections
- autoimmune reactions
- toxins
- trauma
- stress
what is common before a schizophrenic episode?
exposure to stressors
there is a correlation between the amount of _____ and ______ of episode
stress, severity
schizophrenia therefore has a strong environmental component
what are the main 2 drugs for schizophrenia that were discovered by luck?
Chlopromazine
Reserpine
what was chlorpromazine originally sold as?
an anti-histamine, surgeon noticed it calmed normal patients down when used as an anti-inflammatory
what drug was taken from a snake root plant and used to treat mental illness in India?
reserpine
how long do both drugs take to work?
2-3 weeks of medication
symptoms like _______ disease start to emerge when both chlorpromazine and reserpine are taken.
parkinson’s
which drug depletes vesicles so reduces the amount of dopamine that can be released?
reserpine
which drug blocks dopamine receptors so stops dopamine working?
chlorpromazine
how is chlorpromazine an antagonist?
it stops dopamine working by binding to dopamine receptors but has no effect so blocks DA
how does reserpine work?
depletes the brain of DA by bursting the vesicles so DA is returned to the cell so it can’t be released
drugs that reduce dopamine neurotransmission ______ psychotic symptoms
reduce
drugs that increase dopamine neurotransmission ______ psychotic symptoms
produce
taking drugs like cocaine and amphetamines lead to psychosis because they are _______ ________ ________
indirect dopaminergic agonists (increase DA in synapse so block reuptake > more DA means more psychosis)
what is the efficacy of an anti-psychotic drug correlated with?
its ability to bind to DA receptors
lower potency of binding to dopamine receptors =
lower anti schizophrenic potency (not as effective)
what drug was found to be a very potent anti-psychotic medication despite having a low potency of binding to DA receptors?
Haliperidol
what did Haliperidol discover about DA receptors?
there is more than 1 type of dopamine receptor (D1 and D2)
which receptor was found to be the one that affects potency?
D2
there is a ______ correlation between the ability of typical anti-psychotics to bind to D2 receptors and their clinical potency
positive
what is adenlyate cyclase?
enzyme that helps send messages inside the cell
are D1 and D2 positively or negatively coupled to adenlyate cyclase?
D1 = +ly coupled D2 = -ly coupled
what other receptor is similar to D1?
D5
what other receptors are similar to D2?
D3, D4
give an example of an atypical antipsychotic that binds to D4 receptor?
clozapine
drugs that are effective anti-psychotics work on the ___ system
dopamine
which 2 receptors work best on anti-psychosis?
D2 (typical)
D4 (atypical)
what is IBZM?
a radioactive chemical to measure dopamine receptors by measuring receptor density using a PET scan
