dl-9a-Deoxy-9a-methylene-PGI2 (a stable prostacyclin derivative): preliminary pharmacological data.

Carboprostacyclin (dl-9a-deoxy-9a-methylene-PGI2), a new stable PGI2-analogue, has been studied in vitro and in vivo. This analogue relaxes bovine coronary artery (potency ratio to PGI2 = 0.17), inhibits human PRP aggregation induced by ADP (IC50 = 12.5 nM2), deaggregates platelet clumps in cat heparinized blood (ED50 = 10.4 microgram/kg) and raises cAMP content in human PRP, but is less potent than PGI2. It is less potent (about 30 times) than PGI2 in lowering blood pressure in anaesthetized rats, inhibits basal gastric secretion in the rat and is 8 and 6 times less potent than PGE2 in protecting rat gastric mucosa from the lesions induced by stress and ASA, respectively, and about half as potent as PGE2 in protecting intestinal mucosa from damage by indomethacin.