[Action of carbacyclic 13,14-didehydro-analogs of prostacyclin on the contractile activity of the rat stomach muscles].

: The pharmacological activity of bicyclooctane and bicycloheptane analogues of prostacyclin was studied on the rat stomach muscle strip. All the analogues are partial agonists. EC50 of the most active of them, 5E isomer of bicyclooctane analogue, is 2.8.10(-7) M-1.2.10(-7) M. 5E isomers of both bicyclooctane and bicycloheptane analogues with a normal length of alpha-chain are at least by an order of values more active than the corresponding 5Z isomers. At the increase of alpha-chain by one methylene group the activity of 5E and 5Z isomers of bicycloheptane analogue becomes similar.