Behavioral effects of classic antidepressants, fluoxetine and imipramine, and new psychotropic benzopentathiepin TC-2153 (20 mg/kg, per os) were studied on mice differing in the predisposition to catalepsy-noncataleptic AKR strain and cataleptic strains CBA and AKR.CBA-D13Mit76 (D13). Mice of D13 strain was created by transferring the CBA-allele of major locus of catalepsy to AKR genome. In the forced swim test (FST) fluoxetine showed antidepressant effect on mice of all three strains, imipramine was effective only in D13 mice, while TC-2153 produced antidepressant effect on AKR and D13 mice. Unlike to imipramine and fluoxetine, TC-2153 did not produce negative side effects in the open field and elevated plus-maze tests. Thus, TC-2153 produces antidepressant effects similar to imipramine and fluoxetine, without any visible negative side effect on locomotory activity and anxiety. The D13 mice in the FST showed high sensitivity to the studied drugs in comparison to the parent strains and can be used as new genetic model for investigation of the mechanism of antidepressant effects.