What triggers the gallbladder to secrete bile?

The secretion of bile from the gallbladder is primarily triggered by the presence of fatty acids in the lumen of the duodenum. When fat enters the small intestine, it stimulates the release of the hormone cholecystokinin (CCK) from the intestinal mucosa. CCK then signals the gallbladder to contract and release bile into the duodenum. Bile is essential for the emulsification and digestion of fats, aiding in their absorption.

While other factors, such as glucose and proteins, play roles in digestion and metabolism, they do not directly stimulate the gallbladder to secrete bile. The gallbladder’s response is specifically linked to fats, making the presence of fatty acids the most significant trigger for bile secretion.