Effects of 9, 12, 15-octadecatrien-6-ynoic acid on the metabolism of arachidonic acid in platelets and on platelet aggregation.

Published

Journal Article

An acetylenic fatty acid: 9,12,15-octadecatrien-6-ynoic acid (dicranin) was extracted from Dicranum Scoparium and preincubated with platelets which were then stimulated by exogenous arachidonic acid (20:4 n-6). This molecule at 10(-4) M weakly inhibited the cyclooxygenase activity as assessed by measurement of 12-hydroxy-heptadecatrienoic acid (HHT) In contrast, the 12-hydroxy-eicosatetraenoic acid (12-HETE) synthesized by the 12-lipoxygenase was strongly increased by about 650%. The same effects were observed with 10(-5) M and with 10(-6) M of dicranin but to a lesser extent. Platelet hydroxylated dicranin metabolites were also found and the structure of the main compound determined by GC-MS was a 13-hydroxy derivative. Its origin has not yet been elucidated. Platelet aggregation induced by 1 microgram/ml of U46619, a structural PGH2 analogue was completely abolished in the presence of dicranin. Platelet aggregation induced either by thrombin or by arachidonic acid was inhibited by 10(-4) M of dicranin only after preincubation. This observation indicates that the formation of metabolites of dicranin are necessary to effect this inhibition. Dicranin is thus a new inhibitor of platelet aggregation and may prove to be useful for elucidating the effects of 12-HETE in biological systems.

Full Text

Duke Authors

Cited Authors

  • Guichardant, M; Michel, M; Borel, C; Fay, L; Magnolato, D; Finot, PA

Published Date

  • March 1992

Published In

Volume / Issue

  • 65 / 6

Start / End Page

  • 687 - 698

PubMed ID

  • 1636161

Pubmed Central ID

  • 1636161

Electronic International Standard Serial Number (EISSN)

  • 1879-2472

International Standard Serial Number (ISSN)

  • 0049-3848

Digital Object Identifier (DOI)

  • 10.1016/0049-3848(92)90108-m

Language

  • eng