Neurotensin

ISI Order Code:

NT

CPT Code:

83519

Clinical Significance:

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.

Reference Range:

50 – 100 pg/ml

Procedure:

Neurotensin is measured by direct radioimmunoassay.

Expected Turnaround Time: 

7 Business Days

Turnaround time is defined as the usual number of days from the date of receipt of a specimen for testing to when the result is released to the ordering facility.

Report:

Sample Report

Patient Preparation:

Patient should be fasting 10 – 12 hours prior to collection of specimen.  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.

Specimen Collection:

Collect 10mL blood directly into ISI’s Z-tube^TM Preservative and separate as soon as possible. Freeze plasma immediately after separation. Special Z-tube^TM is available from Inter Science Institute. Minimum specimen size is 1 ml.

Please contact ISI for separation using a non refrigerated centrifuge. Contact ISI for details.

The Inter Science Institute Z-tube™ collection and preservative tube is intended  for use with Inter Science Institute’s 5-Hydroxyindoleacetic acid (5-HIAA), Neurokinin A (NKA), Neuropeptide Y (NPY), Neurotensin, Pancreastatin, and Substance P assays only. It has not been validated for use with other in vitro assays. Effects of using this device other than as intended are unknown, and is not recommended.

Important Precaution:

Specimens for this assay must be collected using the Z-tube^TM. Specimens must be shipped frozen; specimens are not stable at refrigerated or room temperatures. No other specimens are acceptable.

Rejection Criteria: 

Gross hemolysis/lipemia/icteric

Special Specimens:

For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.

Shipping Instructions:

Ship specimens frozen in dry ice.

References:

• 1. A Schulkes, P Chick, H Wong, and JH Walsh.  A Radioimmunoassay for Neurotensin in Human Plasma.  Clinica Chimica Acta 125:  49, 1982.
• 2. RE Carraway, SP Mitra, GE Feurle, and NH Hickey.  Presence of Neurotensin and Neuromedin N within a Common Precursor from a Human Pancreatic Neuroendocrine Tumor.  Journal of Clinical Endocrinology and Metabolism  66: 1323, 1988.