Collin Prill

Overconsumption leads to many negative health effects, including increased risk of type II diabetes and cardiovascular disease. This consumption behavior is reinforced by reward and addiction pathways in the brain, including an area of the basal forebrain called the ventral pallidum (VP). Activation of the VP leads to increased consumption, which makes the VP a target for research on overconsumption. Several cell types are present in the VP, with inhibitory GABAergic neurons being the most common cell type. Although the whole VP has previously been targeted in eating experiments, the specific cell types within VP still have an unclear role in consumption, especially with sucrose rewards. Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) are one method of targeting cell types in the brain for specific activation or inhibition of neurons. Here we show that selective activation of VP GABAergic neurons using DREADDs leads to an increase in consumption of sucrose and chow in male rats. Conversely, inhibition of VP GABAergic neurons using DREADDs trends towards a decrease in consumption of sucrose and chow in female rats. The sex difference present in activation and inhibition of these neurons was unexpected and not previously noted in the literature as influencing consumption levels. Additionally, sucrose consumption has not previously been tested in VP GABAergic neuron manipulations. Together, these results support the idea that the VP is involved in modulating eating behavior of multiple reward types (i.e. sucrose and chow). We suggest that future consumption experiments include both male and female subjects to account for these sex differences.