Peptide YY (PYY)

Clinical Significance:
Peptide YY is a 36 amino acid peptide that shares sequential homology with Human Pancreatic Polypeptide (HPP) and Neuropeptide Y.  Peptide YY is found throughout the small intestine.  High concentrations are found in the terminal ileum and colon, being maximal in the rectum.  Smaller amounts have been found in the duodenum and jejunum.  Peptide YY causes intestinal constriction inhibiting jejunal and colonic motility.  It also inhibits pancreatic bicarbonate and protein secretion.  Peptide YY rises in response to food and remains elevated for several hours, with the peak response occurring at about one hour.

Reference Range:
30 – 120 pg/ml

Peptide YY  is measured by direct EIA/ELISA.

Patient Preparation:
Patient should be fasting 10 – 12 hours prior to collection.  Antacid medication or medications that affect intestinal motility should be discontinued, if possible, for at least 48 hours prior to collection.

Specimen Collection:
Collect 10mL blood in special ISI GI Preservative tube yielding special GI plasma and separate as soon as possible.  Freeze plasma immediately after separation.  Special G.I. Preservative tubes are available from Inter Science.  Minimum specimen size is 1 ml.

Important Precaution:
Peptide YY specimens must be collected using the G.I. Preservative.  No other specimens are acceptable.
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.

1. TE Adrian, G-L Ferri, AJ Bacarese-Hamilton, HS Fuessi, JM Polak, and SR Bloom.  Human Distribution and Release of a Putative New Gut Hormone, Peptide YY.  Gastroenterology 89:  1070, 1985.

2. TE Adrian, AJ Bacarese-Hamilton, AP Savage, K Wolfe, HS Besterman, and SR Bloom.  Plasma PYY Concentrations in Gastrointestinal Diseases.  Digestive Diseases Science 29:  35, 1984.