Neurotensin is a 13 amino acid peptide produced primarily by endocrine cells of the ileal mucosa. Physiological actions of Neurotensin include hypertension, vasodilation, hyperglycemia, and inhibition of gastric motility. Its C-terminus is similar to Angiotensin I. It is a potent analgesic affecting hypothermia, muscle relaxation, and decreased motor activity. Pancreatic Polypeptide secretion is strongly stimulated by Neurotensin. Neurotensin appears to cause the release of Luteinizing Hormone-Releasing Hormone and Corticotropin Releasing Hormone effecting the release of Luteinizing Hormone, Follicle Stimulating Hormone, and ACTH but not Thyroid Stimulating Hormone or Growth Hormone. Neurotensin also stimulates pancreatic bicarbonate and intestinal secretion. Neurotensin levels are stimulated by food and Bombesin. Elevated levels have been found in pancreatic endocrine tumors, Oat Cell, Squamous Cell, and Adeno Carcinomas. Elevated levels have been found to cause watery diarrhea.
50 - 100 pg/mL
6 - 12 days
Collect specimen in "Z tube" (red top with preservative), available from MLabs, from a fasting patient (10-12 hour fast). Patient should not be on any antacid medication or medications that affect gastroentero-intestinal function, if possible, for at least 48 hours prior to collection. Following collection place Vacutainer® tube on ice, then centrifuge, aliquot plasma into a plastic vial, and freeze. If possible, discontinue insulin medication prior to collection.
Fasting specimen. Requires special "G.I. Preservative" tube. Place on ice.
Test sent to Mayo Medical Laboratories; performed by Interscience Institute.