Anti-aggregatory effect of prostacyclin (PGI2) in vivo

Prostacyclin (PGI2) when infused intravenously reduced the mortality of rabbits given high intravenous doses of arachidonic acid (AA). Prostaglandins E1 and D2 were ineffective. Indomethacin pretreatment abolished the toxic AA effect. Since the lethal effect of AA is partly due to the formation of platelet aggregates it is concluded that PGI2 is a most potent anti-aggregatory prostaglandin in vivo.