What effect does the ileal brake have on gastric emptying and intestinal transit?

What effect does the ileal brake have on gastric emptying and intestinal transit?

• A. Speeds both gastric emptying and intestinal transit
• B. Slows gastric emptying and intestinal transit
• C. Has no effect on gastric emptying and intestinal transit
• D. Increases intestinal transit

Answer: (B)

The ileal brake is a feedback mechanism that slows gastric emptying and small-intestine transit when fatty acids reach the ileum. When fats reach the distal ileum, enteroendocrine cells release hormones like peptide YY (PYY) and GLP-1. These hormones act to dampen motility and gastric secretions, so the stomach empties more slowly and the small intestine moves contents along at a slower pace. This gives more time for digestion and absorption upstream. Therefore, the effect is to slow both gastric emptying and intestinal transit. It does not speed up these processes, nor is it inert, and it does not increase intestinal transit.

The ileal brake is a feedback mechanism that slows gastric emptying and small-intestine transit when fatty acids reach the ileum. When fats reach the distal ileum, enteroendocrine cells release hormones like peptide YY (PYY) and GLP-1. These hormones act to dampen motility and gastric secretions, so the stomach empties more slowly and the small intestine moves contents along at a slower pace. This gives more time for digestion and absorption upstream. Therefore, the effect is to slow both gastric emptying and intestinal transit. It does not speed up these processes, nor is it inert, and it does not increase intestinal transit.