Gambling Disorder has serious consequences and no medications are currently approved for the treatment of this disorder. One factor that may make medication development difficult is the lack of animal models of
gambling that would allow for the pre-clinical screening of efficacy. Despite this, there is evidence from clinical trials that
opiate antagonists, in particular
naltrexone, may be useful in treating
gambling disorder. To-date, the effects of
naltrexone on pre-clinical models of
gambling have not been evaluated. The purpose of the present study was to evaluate the effects of
naltrexone in an animal model of
gambling, the rat
gambling task (rGT), to determine whether this model has some predictive validity. The rGT is a model in which rats are given a choice of making either a response that produces a large reward or a small reward. The larger the reward, the greater the punishment, and thus this task requires that the animal inhibit the 'tempting' choice, as the smaller reward option produces overall the most number of rewards per session. People with
gambling disorder chose the tempting option more, thus the rGT may provide a model of problem
gambling. It was found that
naltrexone improved performance on this task in a subset of animals that chose the 'tempting', disadvantageous choice, more at baseline. Thus, the results of this study suggest that the rGT should be further investigated as a pre-clinical model of
gambling disorder and that further investigation into whether
opioid antagonists are effective in treating
Gambling Disorder may be warranted.