Dopaminergic neurons in the zona incerta modulates ingestive behavior in rats.

The zona incerta, located in the ventral thalamus, is a site of convergence of signals related to drinking. In the present experiments, agonists and antagonists of dopamine receptors were injected into the ZI of animals deprived of water overnight. Injection of 53 nM dopamine or the D2 dopamine receptor agonist PPHT caused a reduction of water and food intake, while the injection of the D1 receptor agonist SKF38393 had no effect. The current results suggest that dopamine injected into the ZI exerts inhibitory influences on drinking behavior mediated by D2 type receptor.