is a member of the family of
Lipid Molecule s known as
Eicosanoids . When given as a drug it is known as '''epoprostenol'''. (Dorlands) It is produced in
Endothelial Cell s from
Prostaglandin H2 (PGH
2) by the action of the
Enzyme Prostacyclin Synthase . Although prostacyclin is considered an independent mediator, it is called '''PGI
2''' (prostaglandin I
2) in eicosanoid nomenclature, and is a member of the
Prostanoid s (together with the
Prostaglandin s and
Thromboxane ).
The series-3 prostaglandin PGH
3 also follows the prostacyclin synthase pathway, yeilding another prostacyclin, .(Fischer, 1985) The unqualified term 'prostacyclin' usually refers to PGI
2. PGI
2 is derived from the ω-6
Arachidonic Acid . PGI
3 is derived from the ω-3
EPA .
Prostacyclin acts chiefly to prevent
Platelet formation and clumping involved in
Blood Clot ting. It is also an effective
Vasodilator . Prostacyclin's interactions in contrast to
Thromboxane , another eicosanoid, strongly suggest a mechanism of cardiovascular
Homeostasis between the two hormones in relation to
Vascular damage.
Synthetic prostacyclin analogues (
Iloprost , cisaprost) are used intravenously, subcutaneously or by inhalation:
Its production is inhibited indirectly by
NSAIDs , which inhibit the
Cyclooxygenase enzymes COX1 and COX2. These convert arachidonic acid to PGH
2, the immediate precursor of prostacyclin.
Essential Fatty Acid
