Cocaine abuse is a major public health problem in the United States. In the latest national study, the number of people over the age of 12 who are current cocaine users is estimated at 1.6 million, or 0.7% of the total population. In recent years, extensive research has demonstrated that cocaine addiction is associated with neuroadaptations and consequent pathology of reward learning. Chronic cocaine exposure leads to alterations in glutamatergic synapses, including changes in glutamate release, gene and protein expression, and synaptic plasticity. Further elucidating the mechanisms underlying these changes and how they lead lo relapse is the goal of this grant application. More specifically, work utilizing both in vitro slice physiology and in vivo field recordings indicate that repeated exposure to cocaine leads to a decrease in long-term depression within the nucleus accumbens (NAc). Although the exact mechanisms underlying this effect are unclear, existing evidence from the learning and memory field indicates that PKC-mediated AMPA receptor endocytosis is necessary for long-term depression. Additional evidence obtained during the K99 phase of funding indicates that blocking long-term depression, either via potentiating endocytosis via deletion of the anchoring protein glutamate receptor interacting protein (GRIP), or disrupting endocytosis, utilizing a transgenic mouse lacking the PKC phosphorylation site on the AMPA receptor GluA2 subunit, leads to increased reinstatement of drug seeking behavior.
Aims proposed for the ROO phase of the grant will expand upon these findings to examine the role AMPA receptor trafficking in stress-induced reinstatement. This will be acomplished using the two lines of mice described above and examining how manipulating AMPA endocytosis alters stress-induced behaviors as well as physiology. None of the aims of the grant have changed since the original K99 submission, however one aim from the K99 phase has been switched with an already-completed aim from the ROO phase, as discussed in the Research Strategy section.

Public Health Relevance

Cocaine is a major health problem in this country and worldwide. In a recent national study, the number of people over the age of 12 who are current cocaine users is estimated at 1.6 million, almost 1% of the total population. The public health costs incurred as a result of cocaine addiction is upwards of 100 billion dollars annually. The proposed research will be directed towards a mechanistic understand of cue and stress-induced cocaine relapse, using state of the art behavioral and physiological techniques. This project will not only help us better understand what causes addicts to relapse when exposed to drug cues and stressful situations but will identify new pharmacological targets for the treatment of cocaine addiction.

Agency
National Institute of Health (NIH)
Institute
National Institute on Drug Abuse (NIDA)
Type
Research Transition Award (R00)
Project #
4R00DA033372-03
Application #
8974637
Study Section
Special Emphasis Panel (NSS)
Program Officer
Pilotte, Nancy S
Project Start
2015-02-01
Project End
2018-01-31
Budget Start
2015-02-01
Budget End
2016-01-31
Support Year
3
Fiscal Year
2015
Total Cost
$248,317
Indirect Cost
$56,832
Name
Temple University
Department
Physiology
Type
Schools of Medicine
DUNS #
057123192
City
Philadelphia
State
PA
Country
United States
Zip Code
19122
Wickens, Megan M; Bangasser, Debra A; Briand, Lisa A (2018) Sex Differences in Psychiatric Disease: A Focus on the Glutamate System. Front Mol Neurosci 11:197
McGrath, Anna G; Lenz, Jeffrey D; Briand, Lisa A (2018) PKM? in the nucleus accumbens acts to dampen cocaine seeking. Neuropsychopharmacology 43:2390-2398
Wimmer, M E; Briand, L A; Fant, B et al. (2017) Paternal cocaine taking elicits epigenetic remodeling and memory deficits in male progeny. Mol Psychiatry 22:1641-1650
Fosnocht, Anne Q; Briand, Lisa A (2016) Substance use modulates stress reactivity: Behavioral and physiological outcomes. Physiol Behav 166:32-42
Briand, Lisa A; Deutschmann, Andre U; Ellis, Alexandra S et al. (2016) Disrupting GluA2 phosphorylation potentiates reinstatement of cocaine seeking. Neuropharmacology 111:231-241
Ortinski, Pavel I; Briand, Lisa A; Pierce, R Christopher et al. (2015) Cocaine-seeking is associated with PKC-dependent reduction of excitatory signaling in accumbens shell D2 dopamine receptor-expressing neurons. Neuropharmacology 92:80-9
Polter, Abigail M; Bishop, Rachel A; Briand, Lisa A et al. (2014) Poststress block of kappa opioid receptors rescues long-term potentiation of inhibitory synapses and prevents reinstatement of cocaine seeking. Biol Psychiatry 76:785-93