prostacyclin

chemical compound

Also known as: PGI2

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Last updated

July 13, 2026

Quick Summary

Prostacyclin is a naturally occurring lipid compound derived from arachidonic acid. It is a type of prostaglandin, which acts as a chemical messenger in the body, regulating physiological processes and mediating inflammatory and immune responses.1

Prostacyclin is synthesized in the walls of blood vessels and plays a crucial role in preventing unnecessary blood clot formation by inhibiting platelet aggregation. It also acts as a vasodilator, relaxing the muscles in blood vessel walls, which reduces resistance to blood flow and can lower blood pressure. While prostaglandins generally have diverse and sometimes opposing effects depending on the tissue and receptor, prostacyclin's primary functions relate to blood flow and clotting.12

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prostaglandin
Vasodilation and blood clotting
Thromboxanes and prostacyclins play an important role in the formation of blood clots. The process of clot formation begins with an aggregation of blood platelets. This process is strongly stimulated by thromboxanes and inhibited by prostacyclin. Prostacyclin is synthesized in the walls of blood vessels and serves…
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Thromboxanes and prostacyclins play an important role in the formation of blood clots. The process of clot formation begins with an aggregation of blood platelets. This process is strongly stimulated by thromboxanes and inhibited by prostacyclin. Prostacyclin is synthesized in the walls of blood vessels and serves…
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renal system
The role of hormones in renal function
…renal cortex produces PGI₂, or prostacyclin. Renal prostaglandins interact with the renin–angiotensin system in several ways. The renal cortex prostaglandin PGI₂ mediates the increased release of renin in response to decreases in renal blood flow. The angiotensin subsequently formed in the plasma stimulates production of the interstitial and duct cell…
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…renal cortex produces PGI₂, or prostacyclin. Renal prostaglandins interact with the renin–angiotensin system in several ways. The renal cortex prostaglandin PGI₂ mediates the increased release of renin in response to decreases in renal blood flow. The angiotensin subsequently formed in the plasma stimulates production of the interstitial and duct cell…
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Sir John Robert Vane
He also discovered prostacyclin, an important prostaglandin that plays a vital role in the process of blood coagulation.
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He also discovered prostacyclin, an important prostaglandin that plays a vital role in the process of blood coagulation.
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