Psychiatry Flashcards
Serotonin is synthesized from _______ and metabolized by ________.
Serotonin is synthesized from tryptophan and metabolized by monoamine oxidase (MAO).
What is the principal site of serotonergic neuronal cell bodies?
Raphe nuclei in the brainstem
What receptor does ondansetron affect?
Ondansetron is a 5HT3 serotonin antagonist (primarily affects the area postrema).
What receptors do triptans act on?
5HTD1 serotonin receptors to inhibit neuronal transmission and trigeminal neurogenic inflammatory peptide release
Where do dopaminergic neurons originate?
The ventral tegmental area and substantia nigra
What is the major inhibitory neurotransmitter in the brain? How is it synthesized?
GABA is the major inhibitory neurotransmitter in the brain. It is synthesized from glutamic acid by glutamic acid decarboxylase (GAD). This is why GAD dysfunction results in overactivity of the CNS and clinical phenotypes like stiff person syndrome.
What is the difference between GABAa and GABAb receptors? Name one medication that acts on each type of receptor.
GABAa: ionotropic receptor - leads to activation of chloride channels
GABAb: metabotropic receptor - coupled to an inhibitory G protein, inhibiting adenylyl cyclase
Benzodiazepines are GABAa agonists. Baclofen is a GABAb agonist.
Which CNS receptors are activated by glutamate?
NMDA, AMPA, and kainic acid receptors
What is the mechanism of action of memantine?
NMDA antagonist used in the treatment of dementia
What is the role of glycine in the nervous system? Where does it primarily act?
Glycine is an inhibitory neurotransmitter located primarily in the spinal cord, brainstem, and retina. When glycine receptors are activated, chloride enters the neuron.
What are the diagnostic criteria for major depressive disorder?
At least 2 major depressive episodes at least 2 months apart. A major depressive episode is defined as symptoms of depressed mood for 2+ weeks in addition to 2 of several other domains, including sleep, appetite, cognition, energy level, hope.
MUST have significant functional impact for diagnosis.
Persistent depressive disorder is a more chronic form in which patients are depressed more days than not for 2 years (adults) or 1 year (children/ado).
What neurotransmitter is found in the locus ceruleus?
Norepinephrine
Name 5 classes of therapies for depression
- Antidepressant medications
- Therapy
- Electroconvulsive therapy (ECT)
- Transcranial magnetic stimulation
- Vagus nerve stimulation
What regions of the brain are affected in depression?
Dorsolateral prefrontal cortex is hypometabolic.
Orbitofrontal cortex is hypermetabolic.
Subcallosal cingulate gyrus is metabolically overactive in depression; connects the frontal and subcortical regions.
Hypothalamic-pituitary-adrenal axis is thought to be involved: patients with depression have elevated corticotropin-releasing hormone.
Can have hippocampal volume reductions.
Are depressive episodes required to diagnose bipolar disorders?
No. Bipolar I can be diagnosed after a single manic episode and Bipolar II can be diagnosed after a single hypomanic episode (hypomania is distinguished from mania by the fact that in hypomania the patient has insight and is not significantly functionally impaired).
What is a panic attack?
Discrete episode of symptoms including intense fear, palpitations, diaphoresis, trembling, sense of choking, nausea, and dizziness
WITH associated derealization (feeling of unreality), depersonalization (feeling of detachment from self), fearing of losing control and/or dying.
What is obsessive compulsive disorder? In what other disease is it a common comorbidity?
Obsessions and compulsions are time consuming and affect function.
Obsessions: persistent ideas, thoughts, or impulses that provoke significant anxiety and distress
Compulsions: repetitive physical or mental acts that are meant to counteract the distress caused by the obsession.
About 50% of people with Tourette syndrome have OCD.
What distinguishes PTSD from acute stress reactions?
Duration. PTSD symptoms are >1 month, acute stress reactions <1 month.
Name the four classes of medications that are FDA-approved for treatment of anxiety disorders
SSRIs
SNRIs
Azaspirodecanedione class ( = buspirone)
Benzodiazepines
What are positive and negative symptoms in schizophrenia?
Positive symptoms: hallucinations, delusions, disorganized thought
Negative symptoms: blunting, alogia or empty speech, apathy, reduced communicativeness
What is the difference between brief psychotic disorder, schizophreniform disorder, and schizophrenia?
TIME
brief psychotic disorder is < 1 month (commonly after significant stressor or post-partum)
schizophreniform disorder is 1-6 months (2/3 go on to have schizophrenia, 1/3 recover or have other diagnoses)
schizophrenia > 6 months (affects about 1% of the population)
What features distinguish conduct disorder from intermittent explosive disorder?
Conduct disorder is highlighted by lack of empathy or remorse for actions such as chronic and pervasive violation of rules (theft and destruction of property), other’s rights (aggression to people/animals), and age-appropriate societal norms.
Intermittent explosive disorder can be characterized by similar behaviors and outburts, but the patient expresses remorse and regret between episodes.
What is trichotillomania?
Recurrent pulling of one’s hair, leading to gratification
Describe Cluster A personality disorders
“Odd or eccentric”
Paranoid
Schizoid (lack of interest in social relationships/intimacy, and lack of enjoyment of social interaction)
Schizotypal (magical or bizarre thinking, prefer social isolation)
