Pancreatic polypeptide, plasma-994
Test info
Human Pancreatic Polypeptide
PP (Pancreatic Polypeptide,Plasma)
Sham Feeding Study
vagus
- Detection of pancreatic endocrine tumors
- Assessment of vagal nerve function after meal or sham feeding
Sham Feeding Study: Providers must schedule Sham Feeding studies directly with the infusion center. The provider is responsible for providing the sham feeding protocol and test orders to the Infusion Center. Typically, the study involves 4 orders and specimens for Pancreatic Polypeptide collected at baseline and then 30, 60, 90 minutes after sham feeding.
Specimen
The patient should fast for 8 hours prior to sample collection
- Immediately following collection, mix sample thoroughly by gently inverting 8 - 10 times to prevent clotting
- Place specimen on wet ice and keep cold at all times following collection
- Spin
- Transfer plasma to a Screw cap transfer vial/tube (Mayo T914), labelled as EDTA plasma
- Freeze
Frozen (strict) – 90 days
Refrigerated - No
Ambient - No
- Gross hemolysis
- Gross lipemia
Performance
Radioimmunoassay (RIA)
Clinical and Interpretive info
0 - 19 years: not established
20 - 29 years: <228 pg/mL
30 - 39 years: <249 pg/mL
40 - 49 years: <270 pg/mL
50 - 59 years: <291 pg/mL
60 - 69 years: <312 pg/mL
70 - 79 years: <332 pg/mL
≥80 years: not established
Pancreatic polypeptide (PP) is secreted by the pancreas in response to hypoglycemia, ingestion of food, or "sham" feeding (food is chewed, but not swallowed) secondary to vagal nerve stimulation. Secretion is blocked by vagotomy or atropine.
The exact physiologic role of PP is undetermined, although the hormone is thought to be involved in exocrine pancreatic secretion and gallbladder emptying.
Markedly elevated levels are often associated with endocrine tumors of the pancreas (eg, insulinoma, glucagonoma, pancreatic polypeptide-secreting tumor of the pancreas). Patients with diabetes may also have elevated PP levels.
A lack of response to sham feeding may indicate vagal nerve damage (eg, surgery-related nerve damage, autonomic nerve disorders). Extensive pancreatic destruction (eg, chronic pancreatitis, pancreatic cancer) may also result in low basal PP levels and a lack of response to sham feeding.