Gastrin

Gastrin (G) is an important gastrointestinal hormone, mainly secreted by G cells. G cells are mainly distributed in the antrum of the stomach. Metabolic sites are in the kidneys, and serum gastrin is elevated when renal insufficiency occurs. Gastrin secretion is mainly caused by food expansion of the antrum, vagus nerve excitatory reflex promotes its secretion or chemical stimulation by food and its decomposition food increases gastrin release, gastric acid increase and sympathetic nerve stimulation inhibit gastrin secretion. Basic Information Specialist classification: Digestive examination classification: endocrine examination Applicable gender: whether men and women apply fasting: fasting Analysis results: Below normal: Common in type A chronic atrophic gastritis. Normal value: Serum gastrin: 63-211μg/L Above normal: Common in a variety of stomach diseases, such as gastrinoma, stomach and duodenal ulcers and chronic renal failure patients. negative: Positive: Tips: Follow the doctor's instructions, follow the doctor, and cooperate with the doctor. Normal value (137 ± 74) μg / L. Clinical significance Abnormal result (1) Gastrinoma (Zollinger-Ellisonsyndrome) Zhuo-Ai syndrome is the most common endocrine tumor of the pancreas. It is the onset of D-cell proliferation of gastrin in islets, which secretes a large amount of gastrin. , the wall cells are extremely increased. Second, it occurs in the stomach and duodenum. Zhuo-Ai syndrome has the following triads of high gastrinemia, which can be as high as l000pg/ml; high gastric acid output, basic gastric acid>15mmol/h, up to 6 times that of normal people; accompanied by recurrent stomach, ten Multiple ulcers in the duodenum, and mostly refractory ulcers, with chronic diarrhea. (2) Gastric and duodenal ulcer gastrin plays a fundamental or important role in the pathogenesis of gastroduodenal ulcer. Under normal conditions, serum gastrin is high, with an average level of about 160pg/ml. There may be some overlap with the normal range; however, it is significantly increased in the case of eating and other secretion of gastrin. High gastrin is one of the important pathogenesis of gastric ulcer. (3) Chronic atrophic gastritis is classified into type A and type B. Type A is an autoimmune disease, positive for parietal cell antibodies, atrophy of parietal cells, decreased gastric acid secretion, and increased secretion of gastrin from gastric sinus G cells; type B is a non-autoimmune disease, wall cell antibody negative, lesion The site is mainly in the antrum of the stomach, the G cells of the pyloric gland are damaged, and the secretion of gastrin is reduced. Increased serum gastrin in Helicobacter pylori gastritis. There are many factors in the mechanism of Helicobacter pylori stimulation of gastrin, such as increased stimulation of inflammatory cytokines, or increased local pH due to urease produced by Helicobacter pylori, which can increase the release of gastrin in the antrum. Gastrin release was reduced after radical or inhibition of Helicobacter pylori infection. (4) Gastric sinus mucosa hyperplasia after gastric subtotal resection of residual gastric antrum and chronic renal failure can have elevated serum gastrin. Need to check the crowd: gastritis, gastrointestinal pain. High results may be diseases: pediatric gastrointestinal bleeding, thyroid microcarcinoma, pediatric chronic gastritis, chronic gastritis in the elderly, recurrent ulcer, peptic ulcer in the elderly, Zhuo-Ehrlich syndrome, duodenitis, stress ulcer , c islet functional beta cell tumor considerations Before the examination, the release of gastrin is affected by the excitability of the vagus nerve. It is also stimulated by food stimulation, gastric pyloric sinus expansion, and humoral factors. The pH of the gastrointestinal contents has a great influence on the release of gastrin. So patients try to avoid eating food. Requirements for inspection: Follow the doctor's instructions, follow the doctor, and cooperate with the doctor. Inspection process The differential diagnosis of gastrinoma and other diseases with elevated gastrin is as follows: 1 Secretin test: It is the most valuable person in the challenge test, saving time and less adverse reactions. Serum gastrin concentration was measured every 5 minutes after intravenous injection of secretin2U/kg. The serum gastrin value increased to 500pg/ml 5-10 minutes after injection. Secretin can inhibit gastric acid secretion, so gastrin and gastric acid can be reduced, or no change or only mildly elevated, in the gastric sinus G cell hyperplasia and duodenal ulcer patients. 2 calcium infusion test: the use of calcium ions to stimulate tumor release of gastrin. Common calcium gluconate 12 ~ 15mg / kg intravenous infusion, for 3 hours, the concentration of serum gastrin was measured every 30 minutes. The patient often reached the highest peak of gastrin value 3 hours after the instillation, and the increase was often >400pg/ml. Those with hypercalcemia should avoid this test. Duodenal ulcers can be increased in a small amount, and the results of gastric antral G cell hyperplasia have no regularity. 3 standard test test: often 1 piece of bread, 200mL of milk, 1 boiled egg, 50g of cheese (containing 20g of fat, 30g of protein, 25g of carbohydrate) as a standard stimulant. The serum gastrin concentration was measured every 15 minutes after the meal. There was no increase or minimal increase in serum gastrin after the test, and the increase was less than 50% of the fasting serum gastrin. The gastric gastrin in the gastric antrum G cell hyperplasia increased more than 2 times. Patients with duodenal ulcer showed a moderate increase. Not suitable for the crowd Generally no taboos. Adverse reactions and risks Generally not.