The effect of garlic extracts on contractions of rat gastric fundus and human platelet aggregation.

Garlic has been extracted and separated chromatographically into various fractions which show different degrees of activity as inhibitors of platelet aggregation and smooth muscle. The most potent smooth muscle inhibitor fraction had little activity on platelet aggregation, but microgram ml-1 concentrations greatly reduced the contractions of rat gastric fundus to prostaglandin E2 and acetylcholine. Material in this fraction may contribute to some of the claimed therapeutic effects of garlic involving smooth muscle. Its identity is not known, but is different from allyl sulphide, dimethyl sulphide and diallyl disulphide. These compounds eluted earlier on liquid chromatography than the most active fraction, and they showed only modest inhibitory activity against prostaglandin E2 and acetylcholine on rat fundus.