Assessment of Impulsivity and Compulsivity in Taar9 Knockout Rats Using an Addictive Behavior Model

Trace amines and their receptors, in particular TAAR9, can act as potential regulators of the mechanisms of compulsivity and impulsivity, as addictive manifestations of behavior. The aim of this work was to evaluate the impulsive and compulsive components of the behavioral phenotype of rats with TAAR9 gene knockout. The assessment of impulsive behavioral elements was performed using the adapted Iowa Gambling Task (IGT). TAAR9-KO rats did not differ from wild-type rats in the IGT test and equally preferred the option associated with the greatest reward. The marble burying test was used to assess the compulsive component of behavior. The TAAR9-KO group demonstrated an increase in compulsive-like behavior compared to the control in the marble burying test. Thus, TAAR9-knockout rats demonstrate prerequisites for increased compulsive behavior, which is associated with the development of elements of gambling addiction.