Ventral Tegmental Area Microinjected-SKF38393 Increases Regular Chow Intake in 18 Hours Food Deprived Rats

Ventral tegmental area (VTA) dopamine neurons play an important role in reward mechanisms of food intake, and VTA dopamine receptors exist on the terminal of glutamatergic and GABAergic neurons and regulate GABA and glutamate release. To our knowledge, there is no evidence to show that VTA D1 dopamine receptors play a role in regular chow intake. In this paper, the effect of SKF38393, a D1 receptor agonist, was considered on regular food intake in 18 h food deprived-conscious rats. Our results revealed that VTA-microinjected SKF383993 increased regular chow intake in a dose dependent manner. The SKF3833 stimulatory effect persisted over 2 h post-injection. The results showed that the SKF38393, at doses less than 5 µg, did not affect locomotor activities. In summary, the current study suggests that VTA not only affects food reward but is also involved in regulatory mechanisms of regular feeding, at least in part, through dopamine fibers.