Chapter 17: Drugs of Abuse Flashcards
what causes tolerance/decreased response to drug?
neuronal changes and changes in receptors/metabolism
physiological dependence is characterized by ___or ___ effect when the drug is removed
withdrawal symptoms; rebound
why cant beta blockers be abruptly stopped?
the body has become used to their BP lowering effects , causing rebound hypertension
what is psychologic dependence?
drug-seeking behaviour
prescription drugs that have either ___ or ___ effects are often misused
sedative or stimulant
does LSD have a therapeutic use?
no
can LSD be addictive?
no evidence to say it is addictive
t/f not all drugs that are misused are addictive
true
t/f all recreational drugs are addictive
no
there is a link between the activation of ___ pathways in the brain and the development of addiction
dopamine
activation of the mesolimbic dopamine pathways promotes ___ and ___ leading to addiction
reinforcement and reward
t/f different brain regions communicate to determine how we respond to a situation
true
the dopaminergic neurons that are linked to addiction are found in the mesolimbic pathways that runs from the ___ to the nucleus accumbens
ventral tegmental area (VTA)
drugs that cause addictive typically release ___ from the VTA neurons in the nucleus accumbens
dopamine
what happens in terms of addiction and aversion when dopamine is blocked from entering the nucleus accumbens?
has an avoidance effect in animal studies
t/f just blocking the release of dopamine from the VTA will 100% cure addiction
false, not that simple
the dopamine hypothesis of addiction states that all addictive drugs cause an increase in the release of dopamine from the ___ into the ___
VTA into nucleus accumbens
opioids, THC and GHB affect the dopamine release from the VTA by targeting ____ receptors
GPCR
benzodiazepines, nicotine, and ethanol affect the dopamine release from the VTA by targeting ___ receptors
ion channel
cocaine, amphetamine, ecstasy affect dopamine release from the VTA by targeting ___
transporters
drugs may act upstream of the VTA on ___ neurons to cause disinhibition of the dopaminergic neurons
GABAergic
opioids act on ___ receptors of the GABA neuron to reduce the amount of GABA onto VTA
mu opiod
cannabinoids act on ____ receptors of the GABA neuron to reduce GABA release on VTA
CB1
dopaminergic VTA neurons are influenced by inhibitory ___ neurons
inhibitory GABA
where are mu opioid receptors found on GABA and dopaminergic neurons?
GABA= dendrites of cell body dopa= presynaptic terminals
where are CB1 receptors found on GABA neurons?
presynaptic terminals
the mu opioid and CB1 receptors are coupled to a ___ G protein
GI/GO
the GI/GO pathway in GABA neurons stimulated by opioids and cannabinoids is mediated by ____ subunits
G beta-gamma