GABA System, Sedative-Hypnotic & Anxiolytic Drugs - 27 Flashcards
What is GABA an abbreviation for?
Gamma-Aminobutyric Acid
What can drugs that target the GABA system be used for?
Anti-Anxiety, Sedation, Muscle Relaxation, General Anesthesia, Hypnosis (insomnia), Anti-convulsants
What is a sedative?
A drug that decreases activity, moderates excitement and calms the recipient.
What is a hypnotic?
A drug that produces drowsiness and facilitates the onset and maintenance of a state of sleep.
What are examples of Anxiety Disorders?
Panic disorder, Agoraphobia, Social phobia, Specific phobia, Posttraumatic stress disorder, OCD, Generalized anxiety disorder.
What areas of the brain are involved in anxiety disorders?
The amygdala, hippocampus, and cortex
How can anxiety be induced/worsened?
Stress, lack of sleep, chemical dependency (alcohol binge)
Why are some people more susceptible to anxiety disorders?
Anxiety disorders are a product of genes and environmental interactions
Generally, how do anxiety disorders occur?
Over-activation in emotion centers of brain (amygdala, hippocampus, and cortex) - Caused by insufficient GABA transmission (GABA is inhibitory)
What is the primary inhibitory neurotransmitter in the brain?
GABA
How does GABA inhibit neuronal activity?
When it binds its receptor, it opens a Cl- channel - makes more negative/inhibits
What do drugs that potentiate the GABA receptor do?
They make the Cl channel stay open longer.
What is the precursor of GABA?
Glutamate
How many subunits does the GABA receptor have?
- Its a pentamers
Where does GABA bind on its receptor?
At the interface of the Alpha and Beta subunits
Where do Benzodiazepines bind the GABA receptor?
At the interface of the Alpha and Gamma subunit
What effect do barbiturates have on GABAa receptors?
At low concentrations - keeps GABAa receptor open longer when GABA bound :
In high concentrations - directly opens the Cl channel without GABA bound
How can barbiturates be dangerous
In high doses, will suppress so many neurons that will have complete CNS depression - death
What are three common barbiturates? And their relative lipid solubilities.
Phenobarbital (+), Pentobarbital (++), Thiopental (+++)
How does lipid solubility affect the drug?
Affects how fast they get in the CNS, and their duration of action.
What are some therapeutic uses of barbiturates?
Anesthesia, anticonvulsant, anxiety/insomnia (replaced by benzos), 1 time use is acceptable (not a daily medicine)
What effect does P450 have in the liver?
P450s metabolize drugs in the liver.