ABNORMAL PANCREATIC POLYPEPTIDE RESPONSE TO INTRAVENOUS GLUCOSE IN URAEMICS. A POSSIBLE MECHANISM BEHIND IMPAIRED GLUCOSE TOLERANCE IN URAEMIA

Abstract

Glucose handling and insulin secretion were studied in chronic haemodialysis patients and correlated with circulating levels of immunoreactive pancreatic polypeptide (PP). No correlation was found between the elevated basal levels of PP and K-rate or the maximum insulin response after a single intravenous injection of glucose. Fifty-three per cent of the patients had a normal glucose tolerance defined as a K-rate more than 1. This group of uraemics had a tendency to an exaggerated insulin response compared with the controls but no significant changes of serum-PP levels after a glucose stimulus were observed. In contrast, uraemic patients with a K-rate less than 1 and normal insulin response, showed significant increases of serum-PP at 4 and 6 min after glucose administration. Among all uraemic patients we found a significant inverse correlation between the K-rate and the early PP response (P less than 0.05) and a significant positive correlation between the K-rate and early insulin response (P less than 0.05). PP release in response to acute hyperglycaemia may be one mechanism behind impaired glucose handling in uraemics, either by reducing peripheral insulin activity or by preventing insulin secretion sufficient to overcome the decreased tissue sensitivity to insulin.