Relaxant effect of all-trans-retinoic acid via NO-sGC-cGMP pathway and calcium-activated potassium channels in rat mesenteric artery

Am J Physiol Heart Circ Physiol. 2013 Jan 1;304(1):H51-7. doi: 10.1152/ajpheart.00240.2012. Epub 2012 Nov 2.

Abstract

Intraperitoneal injection of all-trans-retinoic acid (ATRA) results in a reduction of blood pressure in spontaneously hypertensive rats. However, the mechanisms involved in this effect are not clear. We hypothesized that ATRA may relax resistance arteries. In this study, we found that ATRA relaxed phenylephrine-preconstricted mesenteric arterial rings, which were abrogated by the removal of the endothelium. Pretreatment of endothelium-intact arterial rings with an inhibitor of endothelial nitric oxide (NO) synthase, N(G)-nitro-l-arginine methyl ester (l-NAME), or soluble guanylyl cyclase, 1H-[1,2,4]-oxadiazole-[4,3-α]-quinoxaline-1-one, reduced the vasorelaxant effect of ATRA. Incubation of mesenteric arterial rings with ATRA increased the production of NO and cGMP, which were blocked by N(G)-nitro-l-arginine methyl ester. The vasorelaxant effect of ATRA was markedly attenuated in the presence of an inhibitor of big conductance calcium-activated potassium channels (charybdotoxin), but not with an inhibitor of voltage-dependent potassium channel (4-aminopyridine) or ATP-sensitive potassium channel (glibenclamide). Activation of retinoic acid receptors (RARs) with CH55 or retinoic X receptors (RXRs) with LGD1069 induced the vasorelaxation of phenylephrine-preconstricted mesenteric arterial rings. The RAR (BMS493) and RXR (UVI3003) antagonists blocked the ATRA-induced vasorelaxation. The vasorelaxant effect ATRA is physiologically relevant because the intravenous infusion of ATRA decreased blood pressure in normotensive rats. We conclude that ATRA relaxes resistance vessels via both RARs and RXRs receptors that are mediated by the endothelium-dependent NO-cGMP pathway, which may participate in the control of blood pressure.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Pressure / drug effects
  • Cyclic GMP / metabolism*
  • Dose-Response Relationship, Drug
  • Endothelium, Vascular / drug effects
  • Endothelium, Vascular / enzymology
  • Enzyme Inhibitors / pharmacology
  • Guanylate Cyclase / metabolism*
  • Infusions, Intravenous
  • Male
  • Mesenteric Artery, Superior / drug effects*
  • Mesenteric Artery, Superior / enzymology
  • Myography
  • Nitric Oxide / metabolism*
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Nitric Oxide Synthase / metabolism
  • Potassium Channel Blockers / pharmacology
  • Potassium Channels, Calcium-Activated / drug effects*
  • Potassium Channels, Calcium-Activated / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Cytoplasmic and Nuclear / metabolism*
  • Receptors, Retinoic Acid / drug effects
  • Receptors, Retinoic Acid / metabolism
  • Retinoid X Receptors / drug effects
  • Retinoid X Receptors / metabolism
  • Second Messenger Systems / drug effects
  • Soluble Guanylyl Cyclase
  • Time Factors
  • Tretinoin / administration & dosage
  • Tretinoin / pharmacology*
  • Vasodilation / drug effects*
  • Vasodilator Agents / administration & dosage
  • Vasodilator Agents / pharmacology*

Substances

  • Enzyme Inhibitors
  • Potassium Channel Blockers
  • Potassium Channels, Calcium-Activated
  • Receptors, Cytoplasmic and Nuclear
  • Receptors, Retinoic Acid
  • Retinoid X Receptors
  • Vasodilator Agents
  • Nitric Oxide
  • Tretinoin
  • Nitric Oxide Synthase
  • Guanylate Cyclase
  • Soluble Guanylyl Cyclase
  • Cyclic GMP