Incubation of Accumbal Neuronal Reactivity to Cocaine Cues During Abstinence Predicts Individual Vulnerability to Relapse.

1. Neuropsychopharmacology. 2018 Apr;43(5):1059-1065. doi: 10.1038/npp.2017.224.
Epub 2017 Sep 18.

Incubation of Accumbal Neuronal Reactivity to Cocaine Cues During Abstinence
Predicts Individual Vulnerability to Relapse.

Guillem K(1)(2), Ahmed SH(1)(2).

Author information:
(1)Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293,
Bordeaux, France.
(2)CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France.

An important goal for the treatment of cocaine addiction is to identify
neuromarkers that can predict individual vulnerability to relapse after
abstinence. There is some evidence that individual reactivity to cue-induced
craving may predict subsequent relapse after a period of abstinence. Here we
sought to identify the neuronal correlates of this predictive relationship in
rats. Rats were trained to self-administer cocaine (6 h) for 16 days to induce
escalation of cocaine intake. Then rats underwent a 1-month period of forced
abstinence after which they were re-exposed to cocaine self-administration (6 h)
for 8 additional days to induce re-escalation of cocaine intake. We recorded
nucleus accumbens (NAc) neuronal responses to drug conditioned stimuli (CS) 1 day
before and after 1 month of abstinence from cocaine intake escalation. Rats were
ranked according to their individual percentage of CS responsive neurons recorded
during the last day of abstinence and split by the median into two groups. We
found evidence for a robust, incubation-like increase in NAc reactivity to
cocaine cues after abstinence only in a subset of individuals (High CS rats).
Importantly, compared with other rats that did not present an incubation of NAc
reactivity to cocaine cues (Low CS rats), High CS rats were faster to re-escalate
their intake of cocaine after abstinence. In addition, after re-escalation, they
worked harder and were less sensitive to risk of punishment than Low CS rats,
indicating a strengthened motivation to seek and/or take the drug in that group
of rats. Overall, these findings indicate that incubation of NAc neuronal
reactivity to cocaine cues during abstinence may constitute a predictive
neuromarker for individual vulnerability to relapse.

DOI: 10.1038/npp.2017.224
PMCID: PMC5854799 [Available on 2019-04-01]
PMID: 28920590

Auteurs Bordeaux Neurocampus