From the Research
The correct answer is (b) stimulates pancreatic enzyme secretion. Secretin is a hormone produced by S cells in the duodenum in response to acidic chyme entering from the stomach. Its primary function is to stimulate the pancreas to release bicarbonate-rich pancreatic juice, which helps neutralize stomach acid in the duodenum. While secretin does stimulate pancreatic secretions, it particularly enhances the watery, bicarbonate component rather than the enzyme component (which is primarily stimulated by cholecystokinin) 1. Secretin actually inhibits gastrin secretion and gastric acid production, not stimulates them as suggested in options (a) and (d) 2. It also has minimal direct effects on intestinal motility, making option (c) incorrect. Some studies suggest that other hormones such as melatonin, leptin, or ghrelin may stimulate pancreatic enzyme secretion by activating the release of cholecystokinin and the duodeno-pancreatic reflex 3. However, the primary role of secretin is to regulate duodenal pH and create an optimal environment for digestive enzymes to function, which is essential for maintaining morbidity, mortality, and quality of life outcomes. Key points to consider include:
- Secretin's role in stimulating bicarbonate secretion
- The distinction between secretin's effects on the watery, bicarbonate component versus the enzyme component of pancreatic secretions
- The inhibition of gastrin secretion and gastric acid production by secretin
- The minimal direct effects of secretin on intestinal motility
- The potential interactions between secretin and other hormones in regulating pancreatic enzyme secretion 4, 5.