May 7 (HealthDay News) -- A new class of weight-loss drugs that suppresses appetite by blocking cannabinoid receptors in the brain should be used with caution in children, U.S. scientists report.

In research with mice, they found this class of drugs also suppresses the adaptive rewiring of the brain necessary for neural development in young animals. The findings are in the May 8 issue of Neuron.

One such drug is rimonabant (Acomplia), which was developed by Sanofi-Aventis and is awaiting approval by the U.S. Food and Drug Administration. Other pharmaceutical companies are developing similar drugs.

In this study, researchers concluded that a cannabinoid receptor-blocking drug called AM 251 affected experience-dependent cortical plasticity in the brains of juvenile mice. This plasticity is the experience-prompted adaptive rewiring of the brain that plays an critical role in the neural development of young animals.

"Our finding of a profound disruption of cortical plasticity in juvenile mice treated with AM 251 suggests caution is advised in the use of such compounds in children," wrote Mark F. Bear and his colleagues, of the Howard Hughes Medical Institute, The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, in Cambridge, Mass.

SOURCE: Cell Press, news release, May 7, 2008