Vascular smooth muscle actions and receptor interactions of 8-iso-prostaglandin E2, an E2-isoprostane

Biochem Biophys Res Commun. 1993 Sep 15;195(2):507-15. doi: 10.1006/bbrc.1993.2075.

Abstract

8-iso-PGE2, an E2-isoprostane, decreased GFR and RPF dose-dependently in rats, but with lesser potency than 8-epi-PGF2 alpha, an F2-isoprostane. This effect was abolished by SQ29,548. 8-iso-PGE2 displaced [3H]SQ29,548 or [125I]BOP binding in aortic smooth muscle cells with the affinity rank order of SQ29,548 > = I-BOP > U46,619 > 8-iso-PGE2 > PGF2 alpha, while it activated phospholipase C with a potency greater than those of I-BOP or U46,619 and lesser than that of 8-epi-PGF2 alpha. We concluded that 8-iso-PGE2 is a renal vasoconstrictor linked to phosphoinositide metabolism. Its vascular smooth muscle contractile actions are likely mediated through activation of putative thromboxane A2 receptor-like "isoprostane receptors."

MeSH terms

  • Animals
  • Aorta, Thoracic / drug effects
  • Aorta, Thoracic / metabolism
  • Aorta, Thoracic / physiology
  • Binding, Competitive
  • Blood Pressure / drug effects*
  • Bridged Bicyclo Compounds / metabolism
  • Bridged Bicyclo Compounds, Heterocyclic*
  • Cells, Cultured
  • Dinoprostone / analogs & derivatives*
  • Dinoprostone / pharmacology
  • Enzyme Activation
  • Fatty Acids, Unsaturated / metabolism
  • Glomerular Filtration Rate / drug effects
  • Hydrazines / metabolism
  • Inositol 1,4,5-Trisphosphate / metabolism
  • Isomerism
  • Isoprostanes*
  • Kidney / blood supply*
  • Kinetics
  • Male
  • Muscle, Smooth, Vascular / drug effects
  • Muscle, Smooth, Vascular / metabolism
  • Muscle, Smooth, Vascular / physiology*
  • Phospholipases / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Prostaglandin / drug effects
  • Receptors, Prostaglandin / metabolism*
  • Receptors, Prostaglandin E
  • Receptors, Thromboxane / antagonists & inhibitors
  • Regional Blood Flow / drug effects

Substances

  • Bridged Bicyclo Compounds
  • Bridged Bicyclo Compounds, Heterocyclic
  • Fatty Acids, Unsaturated
  • Hydrazines
  • Isoprostanes
  • Receptors, Prostaglandin
  • Receptors, Prostaglandin E
  • Receptors, Thromboxane
  • 7-(3-(3-hydroxy-4-(4'-iodophenoxy)-1-butenyl)-7-oxabicyclo(2.2.1)heptan-2-yl)-5-heptenoic acid
  • Inositol 1,4,5-Trisphosphate
  • SQ 29548
  • Phospholipases
  • Dinoprostone
  • 8-isoprostaglandin E2