abnormal circulating hormone level abnormal circulating pancreatic peptide level abnormal circulating pancreatic prohormone level abnormal circulating PP level abnormal circulating pancreatic polypeptide hormone level MPheno.ontology abnormal circulating pancreatic polypeptide level MP:0008459 anomaly in the amount of the 36-amino acid pancreatic hormone in the blood that is secreted mainly by endocrine cells found at the periphery of the islets of Langerhans in response to ingestions, and regulates gastric secretion, gastric emptying, pancreatic enzyme secretion, and appetite