noun, plural: prostaglandins A
A prostaglandin that is a strong vasodilator and derived from prostaglandin E; (13e,15s)-15-hydroxy-9-oxoprosta-10,13-dien-1-oic acid (pga(1)); (5z,13e,15s)-15-hydroxy-9-oxoprosta-5,10,13-trien-1-oic acid (pga(2)); (5z,13e,15s,17z)-15-hydroxy-9-oxoprosta-5,10,13,17-tetraen-1-oic acid (pga(3))
Prostaglandin is an eicosanoid that is derived from unsaturated 20-carbon fatty acids, such as arachidonic acid, through the cyclooxygenase pathway. There are several prostaglandins and they are designated by appending a letter, i.e. from A to I, to indicate the type of substituents found on the hydrocarbon skeleton.
Prostaglandin A (PGA) series is a cyclopentenone prostaglandin. It is a potent vasodilator. It is thought to be a natriuretic hormone. It may be acting as a circulating hormone that controls the reabsorption of sodium by the kidney.1 PGAs are derived from the dehydration of the prostaglandin E series. The rearrangement of the double bond within the cyclopentane ring in PGA gives rise to the prostaglandin B series. PGA1 and PGA2 are examples of PGAs. They are found in many organs and tissues.
PGAs that are analogs or derivatives and do not occur naturally in the body are referred to as synthetic PGAs. They do not include the product of the chemical synthesis of hormonal PGAs.
1 Jones, R. L. (1972). Functions of prostaglandins. Pathobiol Annu. 2:359-80.