Lec 8 Flashcards
What is Nicotine and what does it do?
Nicotine is the primary psychoactive and addictive drug in tobacco.
In the PNS it causes muscle activation and twitching.
In the CNS is causes increased alertness and decreased reaction time.
It activate nicotinic ACh receptors in the Ventral Tegmental area (DA)
More about Nicotine…
Nicotine is not the cause of death in smokers, other chemical components are.
Primary cause of preventable death in the world
Only 5% of each attempt to stop are successful; about the same statistic for heroin.
What is Amphetamine?
Amphetamine and Methamphetamine are synthetic stimulants.
What does Amphetamine and Methamphetamine do?
They block the re-uptake and increase release of Catecholamines.
What are the effects of Amphetamines?
Short term: alertness, euphoria and stamina.
Long term: sleepiness, weight loss, schizophrenic symptoms.
What drugs are used for treating ADHD?
Amphetamine like drugs
Adderall-dextroamphetamine
Ritalin-methylphenidate
Strattera-atomoxetine
Where does stimulant medication increase activity?
Prefrontal cortex, some subcortical regions, and cerebellum. All centers for executive function
What are the cortico-thalamic networks? What does medication do to them?
They control inhibitory attentional and impulse control systems and process internal and external stimuli. ADHD medication stimulates these inhibitory networks.
What are our depressants?
Alcohol, Anxiolytics: Benzodiazepines, Barbiturates
What effects does Alcohol have?
In low doses: Stimulates, turning off cortical inhibition, reducing social constraints and anxiety.
At higher doses: sedative effect
Its’ effects are biphasic
What effect does alcohol have on neurotransmitters?
Glutamate: inhibits
GABA: Acts as GABA-a receptor to increase binding of GABa (which is inhibitory)
The combined effect of Glutamate and GABA is sedation, anxiety reduction, muscle relaxation, inhibited cognitive motor skills.
Pleasurable effects from stimulation of dopamine, opiate, serotonin, and cannabinoid receptors.
Seizures during alcohol withdrawal are due in part to compensatory increase in the number of glutamate receptors over time.
What neurons does alcohol damage?
It damages neurons in the cerebellum and the frontal lobe. BUT they can recover
What do chronic alcohol users have more of and less of?
Chronic alcohol users have less cortical gray matter and have bigger lateral ventricles.
What are the Fetal Alcohol Syndrome Discriminating features?
Short palpebral fissures Flat midface Short nose Indistinct philtrum Thin upper lip
What are the associated features?
Epicanthal folds
Low nasal bridge
Minor ear anomalies
Micrognathia
What are Anxiolytics
Tranquilizers, reduce nervous system activity.
What is our main anxiolytic?
Benzodiazepine agonists act on GABA-a receptors and enhance inhibitory effects of GABA via Cl- influx
What is our endogenous benzodiazepine?
Allopregnanolone
What are barbiturates?
Barbiturates block sodium ion channels on neurons to prevent inflow of sodium ions.
Also increase flow of chloride ions across the neuronal membrane.
What are our anti-depressants?
MAOIs. Tricyclics. SSRIS and SNRIS
What are MAOIs?
They prevent the breakdown of monoamines at the synapse. Accumulation of monoamines is the major action of antidepressants.
Follow a dopamine molecule from vesicle to its release and binding to its destruction by MAO.
What are the two main modern classes of anti-depressants?
Tricyclics (older): increase norepinephrine and serotonin at synapses by blocking their re-uptake into presynaptic axon terminals.
Selective serotonin re-uptake inhibitors (SSRIs) like Prozac or Zoloft cause serotonin to accumulate in synapses, w/ fewer side effects than tricycles.
Also have SNRIs
What modern class of antidepressants has fewer side effects?
Selective serotonin re-uptake inhibitors (SSRIs)
What are antipsychotic (neuroleptic) drugs?
Class of drugs to treat schizophrenia and aggressive behavior
