Hypothalamic Neuronal Activity and Intermediary Metabolism in ob/ob Mice

Ins R. Violante¹, Tiago B. Rodrigues¹, Laura Nieto-Charques¹, Sebastin Cerdn¹

Using a regional ¹³C HR-MAS approach, we compare the metabolic response of the hypothalamus in wild-type and leptin-deficient (ob/ob) mice after [1-¹³C]glucose administration. Mice conditioned by feeding or fasting received [1-¹³C]glucose (20 μmol/g body weight) and, after microwave arrest of cerebral metabolism, two areas of the brain were separated and studied, hypothalamus and remaining brain. Fasting resulted in increased lactate C3 and GABA C2 enrichments in the hypothalamus of both mice, showing that this is not a leptin-dependent effect. Ob/ob mice showed higher glutamate C4 and glutamine C4 enrichments compared to wild-type mice, revealing increased glutamate/glutamine cycling in these animals.