The gastrin stimulation test (synonym: secretin test) is a functional test that should be performed after an abnormal gastrin determination.Gastrin is produced in the mucosa of the stomach and then released into the bloodstream. Via receptors in the stomach, gastrin stimulates the secretion of gastric acid and thus lowers the pH. At the same time, it stimulates the gastrointestinal muscles.Gastrin release is stimulated by gastric distension, roasting substances, caffeine or alcohol, and vagus stimulation.Strongly acidic gastric contents inhibit the release.If increased gastrin is released, it inhibits the secretion of gastric acid.
The procedure
Material needed
- Blood serum
Preparation/implementation
- In the morning fasting (due tocircadian rhythm) twice blood sampling to determine the basal value (interval 15 minutes)→ administration of secretin (2 i.E./kg KG i.v.)→ blood sampling after 2, 5, 10, 15, 30 minutes.
Confounding factors
- Immediate processing or frozen shipping required
Standard values
| Normal reaction | No increase or only a small increase |
| Pathological reaction | Increase by a factor of two or > 200 ng/l |
Indications
- Suspected gastrinoma (Zollinger-Ellison syndrome).
Interpretation
Interpretation of increased values
- Gastrinoma (Zollinger-Ellison syndrome) – usually malignant tumor that originates in the pancreas (pancreas) in two-thirds of cases and leads to increased gastrin production.
Interpretation of an absent or low increase
- Normal gastrin serum levels
- Functional hypergastrinemia
- Retained antral mucosa according to Billroth II.