Effects of glycosylated hemoglobin on vascular responses in vitro

C L Oltman1, D D Gutterman, E C Scott

  • 1Department of Internal Medicine, University of Iowa, Iowa City, USA. coltman@blue.weeg.uiowa.edu

Insights

Glycosylated hemoglobin (GH) did not impair endothelium-dependent vasodilation in coronary, femoral, mesenteric, or renal arteries, suggesting it is not responsible for diabetes-related endothelial dysfunction.

Area of Science:

  • Cardiovascular Physiology
  • Endocrinology
  • Biochemistry

Background:

  • Vascular responses to vasodilators are impaired in diabetes mellitus.
  • Protein glycation, such as hemoglobin glycation, is implicated in diabetes-related vascular abnormalities.

Purpose of the Study:

  • To test if glycosylated hemoglobin (GH) reduces endothelium-dependent vasodilator responses.
  • To determine if GH explains impaired vasodilation observed in vivo in diabetes.

Main Methods:

  • Studied the effect of GH on vascular responses in ventricular microvessels, coronary, mesenteric, femoral, and renal arteries.
  • Utilized pressurized organ chambers for isolated coronary arterioles and isometric ring techniques for artery segments.

Main Results:

  • In ventricular microvessels, 10 nM GH and non-GH attenuated relaxation to acetylcholine; 1 nM did not.
  • In coronary, femoral, mesenteric, and renal arteries, 10 or 100 nM GH or non-GH did not alter endothelium-dependent responses.

Conclusions:

  • Glycosylated hemoglobin (GH) is not responsible for impaired endothelial function in coronary microvessels, coronary, femoral, mesenteric, and renal arteries associated with diabetes mellitus.
Abstract