| abstract |
Luminal cholecystokinin-releasing factor (LCRF) is a cholecystokinin (CCK) releasing protein isolated from rat intestinal secretion. Purified LCRF was characterized by molecular weight, partial amino acid sequence and CCK releasing activity as shown in in vivo studies of anti-LCRF antibodies in blocking the CCK releasing effect of LCRF. Binding studies demonstrated localization in the duodenum, pancreas and in nerve fibers throughout the pancreas, sensory fibers and cell bodies of the nodose ganglia as well as in sympathetic nerve fibers in the adrenal medulla. LCRF appears to be a neuropeptide present in the enteric, parasympathetic and sympathetic nervous systems, but not in the brain. LCRF-IR is also present in enterocytes at the tips of small intestinal villi. Taken together, the studies indicate that LCRF is a neuropeptide that may have several functions in the gastrointestinal systems and other systems. Immunoaffinity studies using antibodies raised to synthetic LCRF1-6 and small intestinal lumen infusion studies indicate LCRF may be the CCK-releasing peptide present in intestinal secretion that mediates negative feedback regulation of pancreatic enzyme secretion and CCK release. LCRF and functionally related species have potential for development for treatment of insulin secretion, gastric and gallbladder emptying and regimens requiring appetite control or suppression. |