# Mechanisms Regulating Cocaine Memory Strength

> **NIH NIH R01** · UNIVERSITY OF PITTSBURGH AT PITTSBURGH · 2020 · $346,500

## Abstract

Project Summary/Abstract
Addictive disorders are a huge burden on both the individual and on society. Unfortunately, there are few
effective treatments, partially due to the persistence of drug-associated memories that drive craving and
relapse. Therefore, recent research has focused on finding ways to reduce the strength of drug-associated
memories to prevent relapse. Memory strength can be reduced by either disrupting the association between a
cue and a drug via extinction or by inhibiting the reconsolidation of the memory after a reminder event. Both
strategies have been effective in preclinical and clinical models, but in some cases, a memory meant to be
weakened, is instead strengthened due to unintentional enhancement of reconsolidation or inhibition of
extinction. In order to address this problem, we have analyzed changes in protein phosphorylation after a
memory undergoes extinction vs. reconsolidation to identify signaling cascades that are selective to either
memory process, or that ideally regulate the two processes in opposite directions. Identification of opposing
signaling events could allow the development of treatments that both enhance extinction and inhibit
reconsolidation, reducing the strength of the drug-associated memories that drive relapse. Our preliminary data
strongly suggest that opposing Ca2+-related signaling events in the basolateral amygdala (BLA) mediate the
reconsolidation vs. extinction of a memory associated with self-administered cocaine. We will expand our
identification of opposing signaling events in Aim 1 of the proposed studies, including increasing the number of
proteins analyzed, expansion of the time course of analysis, and extending the analysis to females. Moreover,
we will follow-up on the exciting findings from our initial study, which include 1) identification of a novel
phosphorylation event on Ca2+ -calmodulin-dependent kinase 2 alpha (CaMKIIα, phospho-serine 331) induced
by extinction and reduced during reconsolidation that functions to inhibit kinase activity, and 2) a general
decrease in protein phosphorylation after extinction, implicating activation of a phosphatase, such as
calcineurin. Our data led us to hypothesize that extinction training, in addition to involving new learning
mechanisms, can also oppose normal reconsolidation processes. We propose that this occurs within the same
circuits via Ca2+-regulated synaptic depotentiation mechanisms. Extinction-induced synaptic depotentiation
and differences in CaMKII and calcineurin signaling have been reported for conditioned fear memories, but
have not been examined for cocaine-associated memories. Thus, using a combination of approaches in Aims
2 & 3, we will determine if CaMKIIα inhibition via S331 phosphorylation, and activation of calcineurin
phosphatase, can reduce cocaine memory strength to decrease cue-induced reinstatement via enhancement
of extinction AND inhibition of reconsolidation. We will also determine if these signaling pathw...

## Key facts

- **NIH application ID:** 9919523
- **Project number:** 5R01DA042029-05
- **Recipient organization:** UNIVERSITY OF PITTSBURGH AT PITTSBURGH
- **Principal Investigator:** Mary M Torregrossa
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $346,500
- **Award type:** 5
- **Project period:** 2016-07-01 → 2022-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9919523

## Citation

> US National Institutes of Health, RePORTER application 9919523, Mechanisms Regulating Cocaine Memory Strength (5R01DA042029-05). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/9919523. Licensed CC0.

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