Send to

Choose Destination
Psychopharmacology (Berl). 2016 Sep;233(18):3437-48. doi: 10.1007/s00213-016-4388-5. Epub 2016 Jul 28.

N-acetylcysteine amide (AD4) reduces cocaine-induced reinstatement.

Author information

Laboratory of Drug Addiction Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland.
Laboratory of Drug Addiction Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland.
Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel.



Chronic exposure to drugs of abuse changes glutamatergic transmission in human addicts and animal models. N-acetylcysteine (NAC) is a cysteine prodrug that indirectly activates cysteine-glutamate antiporters. In the extrasynaptic space, NAC restores basal glutamate levels during drug abstinence and normalizes increased glutamatergic tone in rats during reinstatement to drugs of abuse. In initial clinical trials, repeated NAC administration seems to be promising for reduced craving in cocaine addicts.


In this study, NAC-amide, called AD4 or NACA, was examined in intravenous cocaine self-administration and extinction/reinstatement procedures in rats. We investigated the behavioral effects of AD4 in the olfactory bulbectomized (OBX) rats, considered an animal model of depression. Finally, we tested rats injected with AD4 or NAC during 10-daily extinction training sessions to examine subsequent cocaine seeking.


AD4 (25-75 mg kg(-1)) given acutely did not alter the rewarding effects of cocaine in OBX rats and sham-operated controls. However, at 6.25-50 mg kg(-1), AD4 decreased dose-dependently cocaine seeking and relapse triggered by cocaine priming or drug-associated conditioned cues in both phenotypes. Furthermore, repeated treatment with AD4 (25 mg kg(-1)) or NAC (100 mg kg(-1)) during daily extinction trials reduced reinstatement of drug-seeking behavior in sham-operated controls. In the OBX rats only, AD4 effectively blocked cocaine-seeking behavior.


Our results demonstrate that AD4 is effective at blocking cocaine-seeking behavior, highlighting its potential clinical use toward cocaine use disorder.


Cocaine; Cue; Extinction training; N-acetylcysteine (NAC); NAC-amide, reinstatement; Substance use disorder

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Springer
Loading ...
Support Center