Deep brain stimulation of the nucleus accumbens core and shell differentially reduce quinpirole induced compulsive checking behavior in rats

Abstract

Electrical deep brain stimulation (DBS) is currently studied in the treatment of therapy-refractory obsessive compulsive disorder (OCD). The variety of targeted brain areas and the inconsistency in demonstrating beneficial effects, however, highlight the need for better mapping of brain regions of which stimulation may produce beneficial effects in OCD. The assessment of the effects of DBS in appropriate animal models may contribute to such goal. As currently available data on DBS of the nucleus accumbens (NAc) on OCD-like bahvior in animal models of OCD are in contrast to clinical data and theoretical hypotheses about how the NAc might be pathophysiologically involved in the manifestation of OCD, the present study investigates the effects of DBS on the NAc core and shell, respectively, in the quinpirole (QNP) rat model of OCD. We demonstrate that functional inhibition via DBS of the NAc-shell using 100µA and of the NAc-core using 100 and 150µA reduces QNP induced compulsive checking behavior in rats. We conclude that a functional inhibition of the NAc can antagonize compulsive checking behavior in rats. We further demonstrate that the beneficial effect of DBS on QNP induced compulsive checking behavior differs between the two anatomically and functionally distinct subregions of the NAc, the NAc shell and the NAc core. The NAc may therefore play an important role in the pathophysiology and constitutes a potential target structure in the treatment of OCD.