The mesolimbic dopamine projection to the limbic forebrain is known to be critically involved in responsiveness to rewards. In two experiments, the consumption of palatable weak sucrose solutions by rats was reduced by chronic exposure to mild unpredictable stress. Increases in the levels of dopamine and serotonin and their metabolites were found in the limbic forebrain of stressed rats; these changes were not present in the caudate nucleus or septal area, or in the brains of meal-fed control animals. In the first experiment (7 weeks of stress), specific binding to dopamine D2 receptors was decreased in limbic forebrain; this change was not seen in the second experiment (3 weeks of stress). We discuss the possible role of these changes in mesolimbic dopamine function in the reduced sensitivity to reward that follows exposure to chronic mild stress.