This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Most studies of CART peptides involve injecting the peptide into the brain and studying its effects. Therefore, this complementary project aimed at reducing endogenous CART was initiated. Several siRNAs have been found that, in preliminary experiments, reduce CART peptide levels. Also, injection of viral particles that will express siRNAs long term has been carried out. Useful behavioral studies are being carried out in animals where CART peptide levels have been reduced.