Final answer:
Gastric Inhibitory Peptide (GIP) is a digestive hormone secreted in response to fats and glucose in the small intestine, aiming to prolong digestion for nutrient absorption and regulate blood glucose through insulin secretion.
Step-by-step explanation:
Sources and Actions of Gastric Inhibitory Peptide (GIP)
The Gastric Inhibitory Peptide (GIP) is one of the hormones that play a crucial role in the digestive process. It is secreted by specialized epithelial cells called endocrinocytes, located in the mucosal epithelium of the stomach and small intestine, particularly in response to the ingestion of fat and glucose within the food. GIP serves several functions, including the inhibition of gastric secretions, the slowing of gastric emptying, and the reduction of motility in the gastrointestinal tract. Thereby, it regulates the rate of digestion, especially after the consumption of high-lipid foods, ensuring they have sufficient time to be digested and absorbed.
Stimulus, Secretion Site, Target Organs, and Effects
The primary stimulus for GIP secretion is the presence of fatty and carbohydrate-rich meals in the intestine. Its site of secretion is the small intestine. The target organs for GIP include the stomach, where it inhibits gastric secretion, and the pancreas, where it promotes insulin secretion in a glucose-dependent manner. GIP's effects are to slow down intestinal motility and gastric emptying, which allows more time for the digestion and absorption of nutrients, and to enhance insulin release to manage blood glucose levels after meals.