Plasma neuropeptide Y in impaired glucose tolerance.

Neuropeptide Y (NPY) has been shown to be associated with insulin resistance, since central administration of the peptide induces muscular insulin resistance. NPY also occurs in pancreatic nerves and inhibits insulin secretion. In this study, we examined the plasma NPY levels in 10 women, aged 57-59 years, with impaired glucose tolerance (IGT), which is often accompanied by a combination of reduced insulin sensitivity and impaired insulin secretion. They were 145 +/- 4.1 pmol/l compared with 143 +/- 4.3 pmol/l in 10 age-matched women with normal glucose tolerance (NGT) (NS). Furthermore, the plasma NPY did not correlate with fasting glucose or insulin levels, the 2-h glucose value after a 75 g oral glucose challenge or insulin sensitivity as determined by the euglycemic, hyperinsulinemic clamp technique. This suggests that plasma NPY is not altered in IGT.