The effects of treatment with aspirin and an antithrombotic agent SH1117 upon platelet thrombus formation in living blood vessels.

The work reported here describes an in vivo study, over several days in each animal, of the formation and behaviour of platelet thrombi in injured living blood vessels in response to topically applied adenosine diphosphate in rabbits which have been treated with oral doses of SH1117 alone or together with acetyl-salicylic (ASA) before and after i.v. injection of alloxan. These two substances SH1117 and ASA when given together display a synergism which is similar to that described for dipyridamole and ASA, but the antithrombotic action of SH1117 and ASA seems to be more profound. It may be of significance that oral SH1117 given alone appears to confer a degree of insensitivity of the injured vessel in its response to ADP, as such an effect is not displayed by dipyridamole.