Table 2. GI Hormones With Cells, Sites of Origin, Diagnostic and Therapeutic Uses.
| GI hormone | Cells and sites of origin | Diagnostic use | Therapeutic use |
|---|---|---|---|
| Gastrin | G cells in gastric antrum. | 1) Fasting serum gastrin and secretin suppression test to evaluate hypergastrinemia. 2) Pentagastrin stimulation test for early diagnosis of medullary carcinoma of thyroid. 3) Pentagastrin stimulation test for assessment of completeness of vagotomy. |
|
| CCK | I cells within crypts of Lieberkuhn of duodenum and jejunum. | 1) Diagnosis of gallbladder dyskinesia. 2) Identification of ampulla of Vater during ERCP. |
Endoscopic clearance of choledocholithiasis after ESWL. |
| Secretin | S cells within crypts of Lieberkuhn of duodenum and jejunum. | 1) Secretin test to diagnose pancreatic exocrine insufficiency. 2) Secretin-enhanced MRCP for the diagnosis of pancreatic divisum, early chronic pancreatitis and exocrine pancreatic insufficiency. |
|
| Somatostatin | D cells in islets of Langerhans of pancreas and GI tract. | Octreotide scan to detect and monitor the progress of treatment of neuroendocrine tumors that have somatostatin receptors. | 1) Esophageal variceal bleeding 2) CIPO 3) Pancreatic fistula 4) Refractory and secretory diarrhea 5) Carcinoid crisis 6) Hepato-renal syndrome 7) VIPoma 8) Acromegaly 9) Sulfonylurea poisoning |
| Motilin | Mo cells within crypts of Lieberkuhn of duodenum and jejunum. | Motilin receptor agonist (erythromycin) is used off-label for the treatment of gastroparesis. | |
| Ghrelin or lenomorelin | Ghrelinergic cells in gastric fundus, small intestine, colon, pancreas, lungs, brain. | ||
| Obestatin | Gastric mucosa | ||
| GRP | Submucosa and myenteric plexus of stomach and intestine, intrapancreatic ganglia, hypothalamus and brain stem. | ||
| GIP | K cells in mucosa of duodenum and jejunum. | ||
| GLP-1 | L cells in distal ileum and colon, some in proximal intestine. | 1) GLP-1 mimetics are used in patients with type II diabetes mellitus. 2) Novel agent for the treatment of NAFLD. |
|
| GLP-2 | L cells in distal ileum and colon. | GLP-2 analogue teduglutide is used for the treatment SBS. | |
| Glicentin | L cells in intestine | ||
| Gastric leptin | Gastric chief cells. | ||
| Neurotensin | N cells in ileum and enteric neurons in myenteric plexus. | ||
| Substance P | Myenteric plexus in gut and vagus nerve. | Substance P/NK-1 receptor antagonist aprepitant is used in chemotherapy-induced nausea and vomiting. | |
| Oxyntomodulin | L cells in intestine. | ||
| Uroguanylin | Enterochromaffin cells in duodenum and jejunum | GC-C receptor agonists linaclotide and plecanatide are used in IBS-C and CIC. |
GI: gastrointestinal; CCK: cholecystokinin; ERCP: endoscopic retrograde cholangiopancreatography; ESWL: extracorporeal shockwave lithotripsy; MRCP: magnetic resonance cholangiopancreatography; CIPO: chronic intestinal pseudo-obstruction; GRP: gastrin-releasing peptide; GIP: gastric inhibitory peptide; GLP: glucagon-like peptide; NAFLD: non-alcoholic fatty liver disease; SBS: short bowel syndrome; NK-1: neurokinin-1; GC-C: guanylate cyclase-C; IBS-C: irritable bowel syndrome with predominant constipation; CIC: chronic idiopathic constipation.