Striatal and hypothalamic control of food intake and glucose metabolism

This thesis explores how two important areas of the brain’s reward system, the nucleus accumbens and lateral hypothalamus, control food intake and glucose metabolism. The thesis is further subdivided into three main lines of research. Firstly, the presence and functioning of glucose sensing neurons, a specialized subset of neurons that responds to changes in extracellular glucose concentrations, in the reward system was studied. Secondly, the relationship between opioids and glucose metabolism was explored, by stimulating opioid receptors in the nucleus accumbens and measuring changes in glycaemia, as well as in a literature review that summarized the side effects of opioid administration on glucose metabolism. Lastly, the interacting effects of fat and sucrose consumption were studied in two sets of experiments: one where the stimulating effects of sucrose on fat intake were investigated, and one where the effects of fat intake on calorie sensing by lateral hypothalamic neurons was studied. Altogether, the experiments described in this thesis add to our existing knowledge of how the brain’s reward system controls both food intake, as well as glucose metabolism.