Combination of aripiprazole and ethanol attenuates marble-burying behavior in mice

Obsessive-Compulsive Disorder (OCD) is characterized by absurd, recurrent thoughts (obsessions) followed by certain stereotyped actions (compulsions). 5-Hydroxytryptamine (5-HT) abnormalities may be involved in OCD, and further, cause changes in serotonergic transmission that may have direct or indirect effects on the neuronal firing of other neuromodulators affecting thoughts, feelings and behaviors. Serotonin-related genes that are found in OCD include those coding for the 5-HT transporter (5-HTT) and receptors (5-HT(2A), 5-HT(2B), 5-HT(2C) and 5-HT(1B)) as well the 5-HT enzyme tryptophan hydroxylase. OCD can impair all areas of brain functioning and produce devastating effects on patients and their families. Marble-burying behavior of mice has been employed to study anxiety disorders, including the OCD. The aim of this study was to test the efficacy of aripiprazole and alcohol per se and in combination on marble-burying behavior of mice. A total of 114 male Swiss mice divided in 19 groups were studied. Aripiprazole (0.1 mg/kg, i.p.) per se as well as ethanol (0.1% w/v) per se did not show any anti-compulsive activity. But the combination comprising of ineffective doses of aripiprazole (0.1 mg/kg, i.p.) and ethanol (0.1% w/v) showed significant anti-compulsive activity as reflected by inhibition of marble-burying behavior.