Nitroglycerin-induced S-nitrosylation and desensitization of soluble guanylyl cyclase contribute to nitrate tolerance

Circ Res. 2008 Sep 12;103(6):606-14. doi: 10.1161/CIRCRESAHA.108.175133. Epub 2008 Jul 31.


Nitrates such as nitroglycerin (GTN) and nitric oxide donors such as S-nitrosothiols are clinically vasoactive through stimulation of soluble guanylyl cyclase (sGC), which produces the second messenger cGMP. Development of nitrate tolerance, after exposure to GTN for several hours, is a major drawback to a widely used cardiovascular therapy. We recently showed that exposure to nitric oxide and to S-nitrosothiols causes S-nitrosylation of sGC, which directly desensitizes sGC to stimulation by nitric oxide. We tested the hypothesis that desensitization of sGC by S-nitrosylation is a mechanism of nitrate tolerance. Our results established that vascular tolerance to nitrates can be recapitulated in vivo by S-nitrosylation through exposure to cell membrane-permeable S-nitrosothiols and that sGC is S-nitrosylated and desensitized in the tolerant, treated tissues. We next determined that (1) GTN treatment of primary aortic smooth muscle cells induces S-nitrosylation of sGC and its desensitization as a function of GTN concentration; (2) S-nitrosylation and desensitization are prevented by treatment with N-acetyl-cysteine, a precursor of glutathione, used clinically to prevent development of nitrate tolerance; and (3) S-nitrosylation and desensitization are reversed by cessation of GTN treatment. Finally, we demonstrated that in vivo development of nitrate tolerance and crosstolerance by 3-day chronic GTN treatment correlates with S-nitrosylation and desensitization of sGC in tolerant tissues. These results suggest that in vivo nitrate tolerance is mediated, in part, by desensitization of sGC through GTN-dependent S-nitrosylation.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Arterioles / drug effects
  • Arterioles / physiology
  • Cricetinae
  • Cysteine / analogs & derivatives
  • Cysteine / pharmacology
  • Drug Tolerance / physiology*
  • Enzyme Activation / drug effects
  • Enzyme Activation / physiology
  • Guanylate Cyclase / genetics
  • Guanylate Cyclase / metabolism*
  • Mouth Mucosa / blood supply
  • Mouth Mucosa / drug effects
  • Mouth Mucosa / enzymology
  • Nitrates / metabolism*
  • Nitrates / physiology
  • Nitroglycerin / pharmacology*
  • Receptors, Cytoplasmic and Nuclear / genetics
  • Receptors, Cytoplasmic and Nuclear / metabolism*
  • S-Nitrosothiols / pharmacology
  • Soluble Guanylyl Cyclase
  • Vasodilation / drug effects*
  • Vasodilation / physiology*


  • Nitrates
  • Receptors, Cytoplasmic and Nuclear
  • S-Nitrosothiols
  • S-nitrosocysteine
  • Guanylate Cyclase
  • Soluble Guanylyl Cyclase
  • Nitroglycerin
  • Cysteine