DRUG ABUSE AND ADDICTION Flashcards
definition:
seeking and taking drugs in spite of negative consequences or personal distress, with a varying loss of control
drug abuse/addiction
characterize drug abuse
1.
2.
3.
- a brain disorder
- chronic and relapsing
- powerful but treatable, and usually beatable
describe the self-administration animal model
most drugs abused by humans are self-administered by animals in this model
useful for studying initiation of drug taking, maintenance, and relapse
suggests that drug taking is an innate drive
which research model is critical for understanding biological basis for drug addiction
drug self-administration animal model
self-administration it itself shows what?
an innate “hunger” for some drugs. many species have a vulnerability to drugs
what characteristic of drug addiction does not eliminate humans as the singular species susceptible to this disease?
drug addiction has to do with neurochemical systems in the brain that are shared by many species
how do drugs effect neuronal communication/neurotransmission (fast processes)?
alter release of neurotransmitter
alter receptor interaction
alter removal of neurotransmitter from the synapse
how does cocaine cause rewarding effects?
1) cocaine binds to dopamine transporter and blocks reuptake in mesolimbocortical pathways, thus 2) potentiates dopaminergic neurotransmission, thus 3) cause the rewarding effects of drug
name the two primary brain regions for addiction
nucleus accumbens
ventral tegmental area
amygdala
describe how the brain overrides brain mechanisms
brain can manage availability and action of neurotransmitters, but cannot control drug levels, access to receptors or their duration of action
dopamine receptors are coupled to what?
G proteins
how do drugs change the brain/alter gene expression (cellular mechanism)?
signal transduction mechanisms alter transcription of mRNA, thus altering gene expression/protein levels and the function of the brain
(G-coupled proteins affect PKC initiation, and thus activation of transcription factors that alter gene expression)
definition:
DNA-related changes in gene expression where ther are no mutations
epigenetics
define DNA mutation
a change in a base/ permanent alteration of nucleotide sequence of the genome
what are the two mechanisms of epigenetic change?
- methylation of DNA which prevents translation
- acetylation of histones that results in an opening of the chromatin so that translation/ gene transcription is facilitated
what are the medications for PS abusers?
none approved yet.
often focus on DA to block euphoria, reduce withdrawal and negative mood, lessen cravings, and enhanc eimpaired cortical function
substitute medication useful for curbing illegal cocaine use
RTI-336
how is vaccine treatment work as a medication for substance abuse?
binds drug (cocaine) in the bloodstream, preventing entry into the brain
how (specifically) does cocaine use effect the brain?
cocaine use reduces D2 levels.
*these levels tend to return to normal very slowly
what two components of the mesocorticolimbic pathway regulate natural and biological rewards, including feeding, drinkin, love and sex, as well as conversion of emotion into motivated action?
(important for rewarding properties of cocaine)
- nucleus accumbens
- caudate-putamen
what component of the mesocorticolimbic pathway regulates attention, mood, and emotions, and plays an important role in reward and reinforcement?
amygdala
where in the mesocorticolimbic pathway do DA cell bodies originate?
VTA (ventral tegmental area)
why do drugs have so much power over behavior?
drugs target powerful endogenous reward/reinforcement systems in the brain that are critical for survival