Reduction of vascular tone by introduction of troglitazone to the canine coronary artery

Arzneimittelforschung. 1999 Jan;49(1):26-9. doi: 10.1055/s-0031-1300353.

Abstract

The insulin-sensitizing agent troglitazone ((+/-)-5-[4-(6-hydroxy-2,5,7,8-tetramethylchroman-2-ylmethoxy++ +)benzyl]-2,4- thiazolidinedione, CAS 97322-87-7), has been reported to reduce vascular tone in the rat tail artery. This study was designed to examine whether troglitazone could relax the precontracted canine coronary artery in vitro. Isometric tension of coronary arterial rings was measured, and analysis by Mann-Whitney U-test revealed that significant relaxation was induced even with 1 mumol/l troglitazone. This relaxation was not affected by blocking of NO synthase, cyclooxygenase, the large and intermediate conductance Ca(2+)-activated K+ channel, the ATP-sensitive K+ channel, or the Na(+)-K+ pump. The exact mechanism of the reduction of vascular tone by troglitazone remains unclear. However, the finding that troglitazone acts as a vasorelaxant in the coronary artery may be clinically useful, since troglitazone is mainly used for type II diabetic patients with insulin resistance, which is associated with increased risk for coronary artery disease.

MeSH terms

  • Animals
  • Chromans / pharmacology*
  • Coronary Vessels / drug effects*
  • Coronary Vessels / physiology
  • Depression, Chemical
  • Dinoprost / pharmacology
  • Dogs
  • Female
  • In Vitro Techniques
  • Isometric Contraction / drug effects
  • Male
  • Muscle Relaxation / drug effects
  • Muscle Tonus / drug effects
  • Muscle, Smooth, Vascular / drug effects*
  • Muscle, Smooth, Vascular / physiology
  • Thiazoles / pharmacology*
  • Thiazolidinediones*
  • Troglitazone
  • Vasodilator Agents / pharmacology*

Substances

  • Chromans
  • Thiazoles
  • Thiazolidinediones
  • Vasodilator Agents
  • Dinoprost
  • Troglitazone