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Uncontrolled hypertension, uncompensated type II diabetes, and smoking have different patterns of vascular

Juan Carlos Yugar-Toledo1, Jose Eduardo Tanus-Santos, Maricene Sabha

  • 1Department of Pharmacology, Cardiovascular Pharmacology Laboratory, Faculty of Medical Sciences, State University of Campinas, Unicamp, Campinas, SP, Brazil.

Chest
|March 10, 2004
PubMed

Insights

Uncontrolled hypertension and type II diabetes mellitus impair vascular smooth muscle function, while smoking does not. Uncompensated diabetics show increased plasma nitrite/nitrate, indicating altered nitric oxide (NO) metabolism.

Area of Science:

  • Cardiovascular Physiology
  • Endothelial Function
  • Vascular Reactivity

Background:

  • Vascular reactivity is crucial for cardiovascular health.
  • Endothelial dysfunction is implicated in various diseases.
  • Nitric oxide (NO) plays a key role in vasodilation.

Purpose of the Study:

  • To evaluate vascular reactivity in healthy individuals, heavy smokers, type II diabetics, and hypertensive patients.
  • To assess plasma levels of nitrite/nitrate, cyclic guanosine monophosphate (cGMP), and thromboxane B2 (TX-B2).

Main Methods:

  • Ultrasound measurement of brachial artery diameter before and after reactive hyperemia and glyceryl trinitrate (GTN) administration.
  • Analysis of plasma biomarkers including nitrite/nitrate, cGMP, and TX-B2.
  • Comparison of vascular responses across four participant groups: controls, smokers, diabetics, and hypertensives.

Main Results:

  • Impaired endothelium-dependent vasodilation was observed in smokers, diabetics, and hypertensives compared to controls.
  • Smokers exhibited normal endothelium-independent vasodilation, while diabetics and hypertensives showed impaired responses to GTN.
  • Plasma nitrite/nitrate levels were elevated in diabetics, with no significant differences in cGMP or TX-B2 across groups.

Conclusions:

  • Uncontrolled hypertension and type II diabetes mellitus are linked to impaired vascular smooth muscle reactivity to nitric oxide donors.
  • Smoking did not demonstrate an association with impaired vascular reactivity in this study.
  • Elevated plasma nitrite/nitrate in uncompensated diabetics suggests altered nitric oxide production or inactivation.
Abstract

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