Advanced Dental Admission Test (ADAT)

Which type of cells produce gastric inhibitory peptide (GIP)?

1. S Cells

2. I Cells

3. K Cells

4. Parietal Cells

The correct answer is: K Cells

Gastric inhibitory peptide (GIP), also known as glucose-dependent insulinotropic polypeptide, is produced by K cells, which are located in the lining of the duodenum and jejunum (the first two parts of the small intestine). GIP plays a critical role in the digestive system by inhibiting gastric motility and promoting insulin secretion from the pancreas in response to food intake, particularly when carbohydrates are consumed. The K cells are sensitive to the presence of glucose, fatty acids, and amino acids, which stimulate their secretion of GIP. This response is part of the body's regulatory mechanism to control blood glucose levels after meals by enhancing insulin release, thereby facilitating glucose uptake by tissues. Other cells mentioned, such as S cells, produce secretin, which primarily regulates water homeostasis and neutralizes stomach acid, while I cells are responsible for producing cholecystokinin (CCK), which stimulates gallbladder contraction and pancreatic enzyme secretion. Parietal cells, on the other hand, secrete hydrochloric acid and intrinsic factor, essential for digestion and absorption of vitamin B12, but are not involved in GIP production. Understanding the specific roles of these various cells helps clarify why K cells are responsible for producing GIP