Plasma met-enkephalin levels in diabetic patients: influence of autonomic neuropathy

Metabolism. 1996 Sep;45(9):1065-8. doi: 10.1016/s0026-0495(96)90004-9.


The presence of opioid peptides within pancreatic islets in several animal species and in humans suggests that these peptides could play a role in pancreatic endocrine secretion, influencing glucose metabolism. We measured plasma met-enkephalin (met-Enk) levels in eight neuropathic (four with insulin-dependent diabetes mellitus [IDDM] and four with non-insulin-dependent diabetes mellitus [NIDDM]) and eight nonneuropathic (four IDDM and four NIDDM) diabetic patients to study met-Enk secretion in diabetic patients with asymptomatic autonomic neuropathy. Plasma met-Enk levels were significantly lower in neuropathic compared with nonneuropathic patients both in the IDDM group (28.7 +/- 4.8 v 61.6 +/- 4.1 pg/mL, P < .0025) and in the NIDDM group (26.5 +/- 3.6 v 44.3 +/- 4.6 pg/mL, P < .0125). This study suggests that the presence of neuropathy in diabetic patients, even if asymptomatic, is associated with a significant decrease of plasma met-Enk levels, thus contributing to a worsening of metabolic control under stress conditions.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Adult
  • Diabetes Mellitus, Type 1 / blood*
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetic Neuropathies / blood*
  • Enkephalin, Methionine / blood*
  • Female
  • Humans
  • Male
  • Middle Aged


  • Enkephalin, Methionine