Nitric oxide/cGMP mediates the spasmolytic action of 3,4'-dihydroxy-5,5'-dimethoxybibenzyl from Scaphyglottis livida

Planta Med. 1999 Mar;65(2):109-14. doi: 10.1055/s-1999-14056.

Abstract

Five aromatic compounds, 3,4'-dihydroxy-5,5'-dimethoxybibenzyl (1), batatasin III (2), coelonin (3), 3,7-dihydroxy-2,4-dimethoxyphenanthrene (4), and 3,7-dihydroxy-2,4,8-trimethoxyphenanthrene (5) were isolated from the orchid Scaphyglottis livida (Lindley) Schltr. Compounds 1-5 induced a concentration-dependent inhibition of the spontaneous contractions of the rat ileum with potencies comparable or higher to that of papaverine. The relaxation evoked by compounds 1-4 was blocked by L-NAME, an inhibitor of nitric oxide synthase. It was also demonstrated that 1 increased cyclic GMP content in rat ileum rings. Compound 1-induced elevation of cGMP was inhibited by L-NAME and ODQ, inhibitors of nitric oxide synthase and soluble guanylyl cyclase, respectively. These results indicate that nitric oxide/cGMP formation constitute the signaling pathway in the spasmolytic action of compound 1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bibenzyls / isolation & purification
  • Bibenzyls / pharmacology*
  • Cyclic GMP / physiology*
  • Male
  • Nitric Oxide / physiology*
  • Parasympatholytics / pharmacology*
  • Plants, Medicinal / chemistry*
  • Rats
  • Rats, Sprague-Dawley
  • Rats, Wistar

Substances

  • 3,4'-dihydroxy-5,5'-dimethoxybibenzyl
  • Bibenzyls
  • Parasympatholytics
  • Nitric Oxide
  • Cyclic GMP