Final answer:
Prolonged course of total parenteral nutrition (TPN) is often complicated by decreased CCK release from lack of enteral stimulation.
Step-by-step explanation:
Prolonged course of total parenteral nutrition (TPN) is often complicated by cholecystokinin (CCK) due to decreased CCK release from lack of enteral stimulation. CCK is a hormone that stimulates the release of pancreatic lipase and the contraction of the gallbladder to release bile salts. Without enteral stimulation, the release of CCK is reduced, leading to complications such as impaired digestion and absorption of nutrients.