An enzyme isolated from arteries transforms prostaglandin endoperoxides to an unstable substance that inhibits platelet aggregation

@article{Moncada1976AnEI,
  title={An enzyme isolated from arteries transforms prostaglandin endoperoxides to an unstable substance that inhibits platelet aggregation},
  author={Salvador Moncada and Richard J. Gryglewski and Stuart Bunting and John Robert Vane},
  journal={Nature},
  year={1976},
  volume={263},
  pages={663-665}
}
Microsomes prepared from rabbit or pig aortas transformed endoperoxides (PGG2 or PGH2) to an unstable substance (PGX) that inhibited human platelet aggregation. PGX was 30 times more potent in this respect than prostaglandin E1. PGX contracted some gastrointestinal smooth muscle and relaxed certain isolated blood vessels. Prostaglandin endoperoxides cause platelet aggregation possibly through the generation by platelets of thromboxane A2. Generation of PGX by vessel walls could be the… 
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3,092 Citations

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References

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TLDR
Material causing contraction of the isolated rabbit aorta was released from guinea pig lung following perfusion with arachidonic acid and from human blood platelets after addition of thrombin to induce aggregation and quantitative analyses of the endoperoxides released from the lungs and platelets showed that only a minor part of the rabbit aORTa contracting activity was due to the prostaglandin end operoxides.
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TLDR
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TLDR
Evidence is presented that the more unstable and major component of rabbit aorta contracting substance (RCS) formed in platelets and guinea pig lung is also thromboxane A2.
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    Proceedings of the National Academy of Sciences of the United States of America
  • 1973
TLDR
The smooth muscle-stimulating activity of the endoperoxide ester on the isolated rabbit aortas trip was 4- to 8-times higher than that of the methyl ester of prostaglandin E(2).
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    Proceedings of the National Academy of Sciences of the United States of America
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TLDR
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