Alterations of brain cerebral cortex CCK receptors in the ob/ob mouse

We investigated the binding of CCK to its receptors in the brain and pancreas of the ob/ob mouse, an animal model of inherited obesity. The binding of CCK to its receptors in the cerebral cortex was increased, and Scatchard analyses revealed that this increased binding was due to an increase in the number of receptor sites. By contrast, there was no increased binding to CCK receptors in other brain regions, including the hypothalamus, or to CCK receptors in the pancreas. In the db/db mouse, another animal model of inherited obesity, no changes in CCK binding to its receptors in cerebral cortex and other brain regions were detected. Our study demonstrates, therefore, that the ob/ob mouse has changes in brain CCK receptors and suggests that certain types of obesity in mice could be related to altered CCK binding and action.