Difference in susceptibility to activity-based anorexia in two inbred strains of mice

Food restricted rodents develop activity-based anorexia in the presence of a running wheel, characterised by increased physical activity, weight loss and decreased leptin Levels. Here, we determined trait differences in the development of activity-based anorexia between C57BL/6J and DBA/2J inbred mouse tines previously reported as having tow and high anxiety, respectively. C57BL/6J mice housed with running wheels and exposed to scheduled feeding reduced their wheel activity, in contrast to DBA/2J mice which exhibited increased behavioural activity under these conditions. Food restriction induced hypoleptinemia in both strains, but the decline in plasma leptin was stronger in DBA/2J mice and correlated with increased activity only in that strain. These data suggest that plasma leptin level dynamics rather than hypoleptinemia alone influences the development of activity-based anorexia and that recombinant inbred panels based on these progenitor lines offer opportunities for the identification of molecular determinants for anorexia nervosa related behavioural traits. (c) 2006 Elsevier B.V. and ECNP. All rights reserved.