The Effect of Prostacyclin (PGI₂) on Platelet Behaviour. Thrombus Formation in Vivo and Bleeding Time

Summary

Prostacyclin (PGI²) infused intravenously into anaesthetized rabbits inhibited electrically-induced thrombus formation in the carotid artery, increased bleeding time and inhibited ex vivo platelet aggregation induced by ADP or arachidonic acid. The increase in bleeding time and the inhibition of ex vivo platelet aggregation lasted for as long as the infusion of PGI² was maintained but rapidly disappeared after infusion was stopped.

Prostacyclin is a more potent inhibitor of platelet function, in vivo than prostaglandin E₁ (PGE₁) or prostaglandin D₂ (PGD₂).

The effects of prostacyclin on all parameters studied except blood pressure were potentiated by the concomitant administration of theophylline, a phosphodiesterase inhibitor.

• References

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