Therapeutic and chemical developments of cholecystokinin receptor ligands

Cholecystokinin (CCK) is an important 'brain-gut' hormone located both in t he gastrointestinal (GI) system and in the CNS. At least two different G-co upled high affinity receptors have been identified: the CCK-A and the CCK-B receptors. Although the complex biological role of CCK is, as yet, not ful ly understood, its connection with many different physiological processes b oth at the GI level and at the CNS level is now well established There is m uch potential for therapeutic use of CCK receptor ligands, however, clear i nvestigations have yet to be completed. Several chemical families have been investigated over the last 20 years to find potent, subtype selective and stable CCK receptor agonists and antagonists. The main goal was to discover new therapeutic drugs acting on GI and/or on CNS diseases and also, to obt ain powerful pharmacological tools that could permit a better understanding of the biological role of CCK. Despite promising results from investigatio ns into medicinal chemistry of CCK receptor ligands, the therapeutical appl ications of these ligands still remains to be defined. This article reviews the main biological role of CCK, the therapeutic potential of CCK-A and CC K-B receptor agonists and antagonists and the common compounds from the dif ferent families of ligands.