Which of the following is NOT a function of cholecystokinin (CCK)?

Cholecystokinin (CCK) is a hormone released by the cells of the duodenum in response to the presence of fatty acids and amino acids in the digestive tract. Its primary functions include stimulating gallbladder contraction, enhancing the secretion of pancreatic enzymes, and relaxing the sphincter of Oddi to facilitate the flow of bile and pancreatic juices into the small intestine.

CCK does not increase gastric acid secretion; instead, it actually works to inhibit gastric emptying and secretion of gastric acid. By slowing the rate at which the stomach empties its contents into the duodenum when fat and proteins are present, CCK allows for better digestion and absorption of nutrients.

Therefore, the statement regarding the increase of gastric acid secretion reflects a misunderstanding of CCK’s role in gastrointestinal physiology, making it the correct choice for the function that is NOT associated with this hormone.