Dopaminergic regulation of feeding behavior: I. Differential effects of haloperidol microinfusion into three striatal subregions

Abstract

In the present study, the role of dopaminergic mechanisms within different striatal subregions in feeding behavior was examined in food-deprived (19 h) rats. Specifically, the dopamine (DA) antagonist haloperidol (0, 0.025, 0.25, 2.5 μg/0.5 μl) was infused bilaterally into the nucleus accumbens (N.Acc), the ventrolateral striatum (VLS), or the dorsolateral striatum (DLS), and a microanalysis of ingestive behavior and spontaneous motor behavior was carried out. When infused into the N. Ace, haloperidol increased feeding duration, food intake, and the average duration of a feeding bout. Locomotor activity and drinking behavior were reduced by N.Acc. haloperidol infusion. In contrast, feeding was attenuated when haloperidol was infused into the VLS. Drinking and locomotion were unaffected. Few changes in ingestive behavior were noted following DA-antagonist treatment of the dorsolateral site. It is hypothesized that DA transmission in the N.Acc. normally facilitates switching between different competing behaviors, that the VLS is critical for control of oral motor mechanisms, and that the DLS is minimally involved in modulating ingestive behavior.