Hypothalamic CART is a new anorectic peptide regulated by leptin

The application of molecular biology techniques in studies of appetite regulation and metabolism have increased the number of signalling molecules known to play a role in the central control of mammalian energy homeostasis. For a number of years, researchers at Novo Nordisk have investigated underlying mechanisms of anorexia mediated by transplantable rumours originating from the pancreas(3.8). Using subtraction hybridisation between cell lines established from anorectic glucagonomas and related non-anorectic glucagonomas we have isolated a cDNA that upon sequencing and comparison with the Genbank database proved identical to a previously reported sequence, designated Cocaine- and Amphetamine Regulated Transcript, CART(2). Further analysis of the anorectic and non-anorectic tumour used in this process demonstrated that the expression of CART was not responsible for their different effects on feeding behaviour of the host. However, in a separate series of experiment, hypothalamic CART expression was discovered to be leptin dependent (see below). Therefore, we decided to concentrate on the central nervous system as the arena for regulatory actions of this molecule on feeding behaviour.