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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