Drugs of abuse Flashcards
Olds and Milner 1954
Rewarding sites in the brain found to be medial fore brain bundle. The mesolimbic pathway from the VTA–>NAcc.
Rat intra-cranial self administration
Dichiara and Imperto 1988
Drugs of abuse increase extracellular dopamine concentrations in the NAcc.
Kappa agonists decrease dopamine in the accumbens
Termorshuizen et al., 2005
86% of users relapse to drug taking within 5 years after methadone treated abstinence
Besancon 1993
Rapid transition from abstinence to compulsive drug use at start of relapse period
Shalev et al., 2002
3 major stimuli for relapse:
- taking a small dose of the drug
- stress
- presented with a cue associated with drug taking
Sanchis-segura et al., 2006
Self administration:
Rodents and non-human primates trained to self administer drugs of abuse.
Extinction-lever press not linked with the drug
Reinstatement- stress, cue induced or small dose of drug
Koob, 2008
Negative affect hypothesis
Bruchas et al., 2010
Dynorphin
D1–>cAMP–>CREB–>dynorphin
Kappa agonist
Volkow et al., 1997
PET scanning for D2 receptors
- Cocaine abusers have fewer D2 receptors in the striatum
- Non-addicts given methylphenidate-those that liked it had lower D2 expression
Dalley JW, 2007
Non-addict rats given cocaine.
Those that ‘liked’ it more had lower density of D2 receptors
Nader et al., 2006
PET scanning in monkeys taking cocaine over 12 months- caused a decrease in D2 receptors
Zhang et al., 2007
Nature argument-SNPs
Receptor functions normally but reduced expression levels
Michael Nader
Putting animal in an unrewarding cage:
- isolation
- no toys
- boring food
Chris Bailey
Non-definitive research- drumming group sessions appear to have the best outcomes
Volkow et al., 2011
Addiction (compulsive drug use) is a learned behaviour
Volkow et al., 2006
Imaging data. Video of someone snorting cocaine increases users craving for the drug. Correlated with increased dopamine levels in the NAcc.
vs neutral video (nature scenes)
Dopamine can be the predictor of reward
DiCiaro et al., 1998
Repeated conditioned stimuli presentation with drug can subsequently elicit an electrochemical response when conditioned stimuli are presented alone.
Induce craving and potentially relapse
Harris et al., 2004
CPP study that shows if you inhibit LTP in the VTA (with glutamate receptor antagonist or PKA inhibitors) then you can inhibit the learning of associative drug relates memories.
Rats–>blocked acqusition of morphine CPP when given into VTA immediately after morphine conditioning.
Kantak et al., 2011
Rats associate cue with taking drug
Extinction phase- lever not connected with drug. Now learnt a new memory so lever press goes down.
Kantak et al., 2011
Extinction training with a cognitive enhancer
Kemp et al., 2007
Modulation of glutamate activity (for a cognitive enhancer). Although it is thought lots of sytemms need to be involved
Olney 1994
NMDA binding site thought to be a good target for cognitive enhancers but NMDA agonists are thought to be neurotoxic
Ungless et al., 2001
First paper to show drugs can cause LTP (only in vivo)
Milekic et al., 2006
Suggested amnesic agents can be used to prevent memories from forming.
Reactivate memory with synaptic plasticity inhibited and it can inhibit the memory forming and erase the ones that have already happened
Soeter and Kindt, 2015
spider fear given propranolol
Brunet et al., 2008
PTSD script driven mental imagery of traumatic event
Saal et al., 2003
Morphine, nicotine and ethanol increase AMPA receptors
Sofuoglu at al., 2014
reviewed many different drugs including modafinil and minocycline for use as cognitive enhancers but as such these studies have only included small samples and were related to non-addictive samples.