Regulatory Peptides: Exchange across the Blood-Brain Barrier

Regulatory peptides produced by endocrine cells of the digestive tract and other peripheral organs affect the brain and thereby elicit multiple CNS-dependent effects. For example, more than two dozen of gut peptide hormones are involved in the transmission of satiety signals, opening up alluring prospects of creating anorexigenic drugs. Nevertheless, these agents, known for almost four decades, have not so far received wide application in clinical medicine. Such a protracted delay in application suggests a need for a better understanding of the theoretical conceptualizations underlying peptide regulation. Our mini review attempts to bridge the gap between theory and practice.