CHOLECYSTOKININ-RELEASING AND SECRETIN-RELEASING PEPTIDES IN THE INTESTINE - A NEW REGULATORY INTERENDOCRINE MECHANISM IN THE GASTROINTESTINAL-TRACT

Maintenance of homeostasis in the upper small bowel is a vital process for the body and therefore highly controlled. The enteric nervous sys tem and the endocrine system are the regulators in this process influe ncing each other. The endocrine system in the gut consists of the clas sical hormones [cholecystokinin (CCK, secretin] to evoke motility or s ecretion. They are under control of releasing factors which are probab ly influenced by the enteric nervous system. Diazepam binding inhibito r and luminal CCK-releasing factor are likely candidates for CCK-relea sing peptides in the negative feedback process in the absence of pancr eatic juice. Experimental evidence suggests a secretin-releasing pepti de. Further studies will be needed to determine the physiological role of each of these peptides. Monitor peptide in the pancreatic juice se ems to function as a specific positive enhancement for CCK release. Al l these peptides are inactivated by the proteolytic enzymes during the interdigestive period. The discovery of additional releasing peptides and factors is very likely. (C) 1998 Elsevier Science B.V.