Feeding association between the nucleus of the solitary tract and the ventral tegmental area

Male Sprague–Dawley rats were fitted with two cannulae in the VTA and one cannula in the NTS for co-administration of the μ-opioid receptor agonist DAMGO in one site and the opioid antagonist naltrexone in the other. Injection of DAMGO into the VTA or the NTS stimulated feeding. The increase in food intake after DAMGO injection into the VTA was decreased following injection of naltrexone into the NTS. Furthermore, the increase in food intake after DAMGO injection into the NTS was decreased following injection of naltrexone into the VTA. These results suggest an opioid-mediated feeding association between the VTA and NTS.