test 2 Flashcards
What is considered a negative symptom of Schizophrenia?
Negative symptoms are considered a reduction in normal functions: The five As- Alogia, affective blunting or flattening, asociality, anhedonia, avolition.
What percent of the population is has Schizophrenia?
0.5-1%
What are the five As and what do they mean?
- Alogia- dysfunction of communication; restriction in the fluency and productivity of thought and speech.
- Affective blunting or flattening- restrictions in the range and intensity of emotional expression.
- Asociality- reduced social drive and interaction.
- Anhedonia- reduced ability to experience pleasure.
- Avolition- reduced desire, motivation or persistence; restrictions in the initiation of goal-directed behavior.
What can potentially happen as side effects in using antipsychotic drugs long term?
Antipsychotic drugs cause an increased incidence of obesity and diabetes. Also cardiovascular disease is inferred.
What do all known antipsychotics capable of treating positive symptoms block?
All known antipsychotic drugs capable of treating positive psychotic symptoms are blockers of the dopamine D2 receptor.
Know about the mesolimbic dopamine pathway.
Hyperactivity in the mesolimbic dopamine pathway hypothetically accounts for positive psychotic symptoms.
The mesolimibic dopamine pathway, which projects from the ventral tegmental area in the brainstem to the nucleus accumbens in the ventral striatum is involved in regulation of emotional behaviors and is believed to be the predominant pathway regulating positive symptoms of psychosis. Specifically, hyperactivity of this pathway is believed to account for delusions and hallucinations.
What is Glutamate?
Glutamate or glutamic acid is a neurotransmitter which is an amino acid. Its predominant use is not as a neurotransmitter but as an amino acid building block for protein biosynthesis. Glutamate is the major excitatory neurotransmitter in the central nervous system and sometimes considered to be the “master switch” of the brain, since it can excite and turn on virtually all CNS neurons.
Know what Stahl says about neurodevelopment and schizophrenia.
Schizophrenia may be caused by neurodevelpmental abnormalities in the formation of glutamate synapes at a specific site: namely at certain GABA interneurons in the cerebral cortex. Something appears to be wrong with the genetic programming of those particular GABA interneurons that can be identified in prefrontal cortex as containing a calcium binding protein called parvalbumin. Theses parvalbumin containg GABA interneurons appear to be faulty postsynaptic partners to incoming glutamate input from pyramidal neurons in prefrontal cortex, and to form defective NMDA receptor containing synaptic connections with incoming pyramidal neurons . Just read the section starting on page 108
How are genes turned on and off by the environment?
a person may have multiple genetic risk factor and exposed to life stresses (abusive childhood, virus or toxin, marijuana, traumatic life events) that change the “biased” circuit. This leads to decompensation and the circuit becomes hypoactivated with unsuccessful compensation. This leads to several symptoms: hallucinations, delusions, thought disorder. page 118
What are atypical antipsychotics approved to treat?
schizophrenia, manic and depressed phases of bipolar disorder, augmenting agents for treatment resistant depression.
What happens when a substantial number of D2 receptors are blocked in the brain?
Psychomotor slowing, emotional quieting, and affective indifference—Neuroleptsis
EPS is also caused by blocking D2 receptors.
Know the various brain pathways that are affected by treatment in schizophrenia.
The mesolimbic dopamine pathway of untreated schizophrenia is hypothesized to be hyperactive and is targeted in schizophrenia treatment.
The mesocortical, nigrostiatal and tuberoinfundibular D2 receptor pathways are impacted negatively with conventional antipsychotic symptoms.
What is Tardive Dyskinesia?
Tardive Dyskinesia is a hyperkinetic movement disorder causes facial and tongue movements, such as constant chewing, tongue protrusions, facial grimacing, and also limb movements that can be quick, jerky or choreiform (dancing). About 5% of patients maintained on conventional antipsychotics will develop tardive dyskinesia every year (about 25% every five years).
Know about extrapyramidal symptoms.
EPS is motor symptoms that occur from blocking D2 receptors in the nigrostriatal pathway which is part of the extrapyramidal nervous systems. Patients who develop EPS early in conventional antipsychotic symptoms are twice as likely to develop tardive dyskinesia if treatment persists.
What is neuroleptic malignant syndrome?
Neuroleptic malignant syndrome is associated with extreme muscular rigidity, hegh fevers, coma, and even death and possibly related in part to D2 receptor blockade in the nirostriatal pathway can also occur with conventional antipsychotic agents.
What causes hyperprolactinemia?
Dopamine D2 receptors in the tuberinfundibular DA pathway are also blocked by conventional antipsychotics and this causes plasma prolactin concentrations to rise. A condition called hyperprolactinememia. It is associated with galactorrhea (breast secretions) amenorrhea, fertility problems, and possibly bone demineralization in older woman not on estrogen.
What are the side effects of anticholinergic agents?
Constipation, blurred vision, dry mouth, drowsiness
read page 139 for what happens with antichlinergic agents.
What makes an antipsychotic atypical?
They are atypical from what is expected of conventional antipsychotics. They have a clinical profile of equal positive antipsychotic actions but low EPS and hyperprolactinemia symptoms.
Know the side effects when medicines work on histamine H1 receptors, alpha 1 aderenergic recptors and muscarinic receptors.
Weight gain and drowsiness is side effects with the histamine receptors.
Cardiovascular disease and orthostatic hypotension are side effects of the alpha 1 aderenergic receptors.
Blocking muscarinic receptors cause dry mouth, blurred vision, constipation, and cognitive blunting.
What is the abbreviation for Serotonin?
5-hydroxytryptamine, 5HT
Blocking which receptor improves learning and memory in experimental animals?
5HT6
What is a partial agonist?
A partial agonist binds in an intermediary manner. It binds “just right” not to hot or to cold. THey are sometimes called “goldilocks drugs.
Which two atypical antipsychotics have the highest metabolic risk?
Clozapine, olanzapine
